- Type of paper
: Paper in journal
Title: Role of the polyurethane component in the adhesive
composition on the hydrolitic stability of the adhesive
- Authors:
- Kovačević, Vera (74041)
- Šmit, Ivan (47636)
- Hace, Drago (15006)
- Sućeska, Muhamed (186903)
- Bravar, Mladen (5281)
- Mudri, Irinej (164763)
Journal: Int.J.Adhesion and Adhesives
ISSN: 0143-7496
Volume: 13
Year: 1993
Pages: from 126 to 136
Language: engleski
Summary: In polyurethanes based on linear polyol,isocyanate and a
chainextender,the physical morphology of adhesive seems to play animportant
role in its overall strength characteristics.The aim ofthis paper is to
examine how the morphology and phase separationof such polyurethane
components affect the adhesive propertiesbefore and after hydrolysis.It is
shown that effective microphaseseparation and the development of
hydrogen-bonded structures,aswell as hydrolytic events in the hard segment
domains,dependstrongly on the adhesive composition.The influence of
theenvironment on polyurethane adhesives can be countered byappropriate
selection of the polyurethane component.
Keywords: polyurethanes,adhesive properties,morphology,phase separation,hydrogen bonding,hydrolysis
- Type of paper
: Paper in journal
Title: Effect of new synthetic product for fatting and bleaching
on the lightfastness and mechanical properties of leather
- Authors:
- Kovačević, Vera (74041)
- Mladinić, Biserka (182041)
- Morović, Ljiljana (197725)
- Bajza, Željko (140705)
- Čavara, Luka
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 41
Year: 1992
Pages: from 125 to 127
Language: hrvatski
Summary: In the paper the relevant literature references about
subjectwere presented.The new product for the fatting and bleaching
ofleather was described(KutrilixB3).The product assures the highgrade of
whitness and the fastness on the aging and degradationof leather.Examined
colour degrees and mechanical properties byusing comparative methods give
the conclusions about the effectsof new sinthesized product on leather
behaviour.
Keywords: leather processing,new product for fatting and bleaching of leather,whiteness degree,yellow degree,mechanical properties of leather
- Type of paper
: Paper in journal
Title: Creation and the construction of the patterns for the
shoes using CAD/CAM system
- Authors:
- Tucaković-Mujagić, Ljiljana (69102)
- Kovačević, Vera (74041)
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 41
Year: 1992
Pages: from 131 to 134
Language: hrvatski
Summary: The authors are described the possibilities of the creation
andconstruction of the shoe patterns using CAD/CAM system.Thissystem
represents the rationalisation in the shoe production.Theworld situation
and achivements as a result of scientific andresearch institutes are
presented.Experimental work is done on asample of shoe model with all
possibilities of corrections.Theconclusion about using CAD/CAM system in
Croatia are drawn.
Keywords: CAD/CAM system,creation and construction of model,rationalisation of shoe production,model corrections
- Type of paper
: Paper in journal
Title: Influence of fatliquoring on water absorption and leather
strengths
- Authors:
- Bajza, Željko (140705)
- Kovačević, Vera (74041)
Journal: Leder und Hautemarkt
ISSN: 0447-D
Volume: 46
Year: 1993
Pages: from 20 to 24
Language: njemački
Summary: It is the objective of leather processing to achive
optimumproperties.Both the structural,chemical,physical and
mechanicalproperties of leather as well as the execution of the
treatmentprocesses influence the leather quality.In this project
theinfluence of the fat level and type of fet on the leatherfirmness and
water uptake is researched-two of the most importantleather properties in
its use.
Keywords: leather processing,structural,chemical,physical,mechanical properties,leather quality,water uptake
- Type of paper
: Paper in journal
Title: Substitution and application of finishes in the footwear
industry
- Authors:
- Stanojević, Duško (157596)
- Kovačević, Vera (74041)
- Babić, Rudi
- Strohal, Tatjana
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 40
Year: 1991
Pages: from 8 to 12
Language: hrvatski
Summary: In the paper several ways of film forming from water
dispersionsbased on polyacrylates and polyurethanes
wereinvestigated.Importance of particles along withflexibility,strength and
toughness depend on finishcomposition.Several samples of finishes based
onpolyacrylate,copolymer acrylate-styrene and combinations ofpolyacrylates
and polyurethanes various formulations wereexamined.Effects on leather were
determined and the conclusionsabout optimal compositions of leather
finishes were drown.
Keywords: leather finishes,polyacrylate,polyurethane,copolymer acrylate-styrene
- Type of paper
: Paper in journal
Title: Phenomenology of leather strength
- Authors:
- Agić, Ante (137300)
- Bajza, Željko (140705)
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 41
Year: 1992
Pages: from 12 to 14
Language: hrvatski
Summary: In the paper leather as anisotropic composite material with
verycomplicated stress-strain fenomenology was described bymodels.Mehanisms
of gas diffusion were explained.The conclusionabout micromechanics and
modern experimental methods forinvestigation of physical properties of
leather was drawn.
Keywords: leather,composite material,gas diffusion
- Type of paper
: Paper in journal
Title: Investigation of the depending effects on the
fatliquoring,dying and defating by the usage of essential factors which
influence their application
- Authors:
- Bajza, Željko (140705)
- Vuković, Tomica (78506)
- Bravar, Mladen (5281)
- Kovačević, Vera (74041)
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 41
Year: 1992
Pages: from 5 to 7
Language: hrvatski
Summary: In the paper the influence of the quantity of the fatting
agentson the leather dying and the possibility of dying by lowtemperatures
were investigated by measurements of dying agents absorbance.The
conclusions about reactions with leatherstructure in optimal processing
were drawn.
Keywords: leather,fatliquoring,defating
- Type of paper
: Paper in journal
Title: Nonionic tensides for degreasing of leather
- Authors:
- Morović, Ljiljana (197725)
- Mladinić, Biserka (182041)
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 42
Year: 1993
Pages: from 104 to 106
Language: hrvatski
Summary: In the work the advantages and failings of the
leatherdegreasing with organic solvents were described.Theinvestigations of
degreasing with tensides the products ofenterprise Kutrilin,were
provided.The results showed that theconcentration of tensides,the
temperature and the processduration had important role in the degreasing
processes.
- Type of paper
: Paper in journal
Title: Quality control of adhesives and cemented shoes
- Authors:
- Kovačević, Vera (74041)
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 42
Year: 1993
Pages: from 107 to 109
Language: hrvatski
Summary: Methods of adhesive joint strength investigations and
variousmaterials which are used in cemented shoes are
mostlystandardised.Environment influence is also necessary to be takeninto
account in defined conditions.In this way the conclusionsabout the quality
of adhesives and/or cemented shoes could bedrawn.
Keywords: quality control,adhesives,cemented shues
- Type of paper
: Paper in journal
Title: Possibilities of the processing the sheep skins
- Authors:
- Kovačević, Vera (74041)
- Bajza, Željko (140705)
- Babić, Rudi
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 42
Year: 1993
Pages: from 109 to 111
Language: hrvatski
Summary: The aim of the paper was to give the possibilities of
newdirections in research and exploatation of raw materials inCroatia based
on ship products.Manufacturing of ship skins fromeconomical and ecological
points of view could be veryinteresting.In the work the specific production
with chosenproducts for leather of ship, were described.
Keywords: Sheep leather
- Type of paper
: Paper in journal
Title: Water repellent leather for special purposes
- Authors:
- Kovačević, Vera (74041)
- Babić, Rudi
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 42
Year: 1993
Pages: from 127 to 128
Language: hrvatski
Summary: In the paper several samples of before hydrofobed leather
wereexamined with the aim of achieving the water resistance but alsowith
good transfering of air and wapour.The best results couldreveal the
mechanisms of open hydrofobing with chosen hidrofobicagent and
comfortability of shoe depends on this properties.
Keywords: hydrofobic leather,hydrofobic agents,water resistance of leather,gas transparence
- Type of paper
: Paper in journal
Title: Promotion of the neutralising and fatting processes of
leather using the Kutrilin agents
- Authors:
- Mladinić, Biserka (182041)
- Pucarević, Z
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 42
Year: 1993
Pages: from 128 to 130
Language: hrvatski
Summary: Research program of Kutrilin enterprise is concentrated
inadustement to requirements and needs of users.The properties ofthe
product for neutralisation(Kutritan 5) and the applicationwere
described.The fatting agent was also examined(KutripolLI)for special soft
leathers.Stabilised composition for leatherfatting could assure good
connecting reaction with leather,so asthe adequate properties.
Keywords: Kutrilin enterprises,research program,neutralisation agent,fatting agent,soft leather
- Type of paper
: Paper in journal
Title: Application of CAD/CAM system in the network with
dislocated units
- Authors:
- Tucaković-Mujagić, Ljiljana (69102)
- Kovačević, Vera (74041)
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 41
Year: 1992
Pages: from 107 to 112
Language: hrvatski
Summary: In the paper experimental results on 2D and 3D system
forselected model of shoe was given and explained in detail.The rateand
accuracy of dates transfer in DGT file possibly connectedwith dislocated
units is very important factor in up to date shoeindustry and it assures
the production quality with the greatmaterials and time savings.
Keywords: CAD/CAM system in footwear industry,modelling,grading,patterns
- Type of paper
: Paper in journal
Title: Production of the white and light leather
- Authors:
- Morović, Ljiljana (197725)
- Kovačević, Vera (74041)
- Bajza, Željko (140705)
- Mladinić, Biserka (182041)
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 41
Year: 1992
Pages: from 27 to 30
Language: hrvatski
Summary: In the paper the factors which influence on the whiteness
andfastness on the light of leather were described.The influences ofthe
fatting agent stabilised with UV absorber as well as newsinthesized optical
bleaching agent were investigated.Theconclusions lead to optimal leather
processing according theresults of whiteness before and after irradiation.
Keywords: leather whiteness,light fastness,products for leather manufacturing
- Type of paper
: Paper in journal
Title: Leather industry and ecology
- Authors:
- Rusan, Zvonimir (149101)
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 42
Year: 1993
Pages: from 79 to 84
Language: hrvatski
Summary: The most important pollutants in leather industry was
describedand documented by tables.Authors gave some solutions of
theseproblems with the changing of some parts of the
technologicalprocess.In conclusions was stressed the importance of
ecologicalproblem solutions in our leather industry.
Keywords: leather industry,ecology,pollutants
- Type of paper
: Paper in journal
Title: Indications of the elements which influence on the
adhesive strength of the materials
- Authors:
- Kovačević, Vera (74041)
- Ažman, J
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 42
Year: 1993
Pages: from 84 to 86
Language: hrvatski
Summary: Various factors as strength,elasticity and hardness
ofmaterials are of importance in adhesive joint strength so as therate of
adhesive strength investigations,and they were explainedand examined in
this paper.The results of investigations showedthat with higher degree of
crosslinking agent in polyurethane andpolychloroprene shoe adhesives
optimal crosslinking could bereached but also increase of viscosity and
lowering of adhesivestrength above this concentration of crosslinking
agent.
Keywords: adhesive strength of materials,adhesives for shue cementing,adhesives based on polyurethane and polychloroprene
- Type of paper
: Paper in journal
Title: New chalenge and necessity in the shuemaking-"quick
response"only withcomputer aided manufacturing
- Authors:
- Kovačević, Vera (74041)
- Agić, Ante (137300)
- Tucaković-Mujagić, Ljiljana (69102)
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 40
Year: 1991
Pages: from 82 to 83
Language: hrvatski
Summary: Specific market demands for fashion,quality and different
kindsof the shoes are bigger and therefore it is necessary
"quickresponse"on these demands.Computer aided manufacturing withspecial
CAD system using 2D and 3D techniques is the best answeron these
demands.The above conclusion is the result of EuropeanFootwear Research
Institutes and our own work planes on CAD/CAMsystem.
Keywords: shue market demands,quality,CAD/CAM in footwear industry
- Type of paper
: Paper in journal
Title: Development and possibilities of the CAD/CAM/CIM systems
in the leather processing industry
- Authors:
- Kovačević, Vera (74041)
- Tucaković-Mujagić, Ljiljana (69102)
- Štimac, S
- Mudri, Irinej (164763)
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 41
Year: 1992
Pages: from 33 to 34
Language: hrvatski
Summary: The ways of CAD/CAM/CIM application in the world was
describedwith the aim of computer integrated manufacturing realisation
inthe shoe industry.The plans about the way of including the 2Dsystem in
Croatian shoe industry was given in detail.
Keywords: leather processing industry,CAD/CAM/CIM application
- Type of paper
: Paper in journal
Title: Investigation of the Influence of Fillers on the
Properties of Poly(vinyl acetate) Adhesives
- Authors:
- Kovačević, Vera (74041)
- Lučić, Sanja
- Hace, Drago (15006)
- Šmit, Ivan (47636)
- Bravar, Mladen (5281)
- Glasnović, A
Journal: J.Adhesion
ISSN: 0021-8464
Volume: 47
Year: 1994
Pages: from 201 to 215
Number of references: 17
Language: engleski
Summary: The properties of poly(vinyl acetate) compositions prepared
as potential wood adhesives were investigated. The paper presents the
results of the influence of various kinds of inorganic fillers based on
calcium carbonate and alumino-silicate and an organic filler, starch, on
the adhesive composition properties. The comparison among rheological
behavior of the adhesive disper-
sions concerntng the specific role of fillers were made. Mechanical and
relaxation properties of the adhesive films could reveal the effect of
filler characteristics on the polymer matrix. The significant influences of
particle size distribution and specific surface area on the poly(vinyl
acetate) adhesive composition were determined, along wth other filler
characteristics.
Keywords: Poly(vinyl acetate) adhesives, fillers, calcite, alumino-silicates, starch, wood adhesive joint
- Type of paper
: Paper in journal
Title: Correlation Between Mechanical Properties and Degradation
Processes of Poly(methyl methacrylate co-butyl acrylate) Films
- Authors:
- Leskovac, Mirela (175223)
- Kovačević, Vera (74041)
- Stanojević, Duško (157596)
- Bravar, Mladen (5281)
Journal: J.Appl.Polym.Sci.
ISSN: 0021-8995
Volume: 53
Year: 1994
Pages: from 1717 to 1721
Number of references: 13
Language: engleski
Summary: Copolymer systems based on various molar ratios of methyl
methacrylate (MMA)/butyl acrylate (BA) and different mass content of
N-methylolacrylamide
(NMA), as a cross-linking agent, were investigated. The influence of
temperature,150oC, under conditions similar to those used in the textile
industry, and effect of ultraviolet (UV) irradiation were examined. The
changes of mechanical properties were found to be connected with the
cross-linking and/or degradation mechanisms. The effect of copolymer
composition on the mechanical properties was established, especially during
UV degradation.
Keywords: Copolymer systems poly(methyl methacrylate co-butyl acrylate),influence of temperature,UV irradiation,mechanical properties
- Type of paper
: Paper in journal
Title: Mechanical Properties,Rheology and Morphology of Composite
Film Blends containing Poly(vinyl acetate) and Filled with Calcite
- Authors:
- Kovačević, Vera (74041)
- Lučić, Sanja
- Hace, Drago (15006)
- Glasnović, A
Journal: Polym.Eng.Sci.
ISSN: 0032-3880
Volume: 35
Year: 1995
Number of references: 13
Language: engleski
Summary: This study investigated the mechanical and rheological
behavior of poly(vinyl-acetate) PVAC composites filled with calcite as a
function of filler particle geometry,particle size distribution and active
surface area. The study of deformation and failure process and their
relation the structure, the mechanism and strength of interaction,provide
useful information to the development of PVAc composites commonly used as
adhesives with improved properties in practice. Detailed morphological
characteristic were made. Tensile properties of PVAc composites evaluated
in the composition range 5-20 wt. % calcite. As expected the breaking
elongation decreased as an effect of matrix mobility restriction by filler
particles interactions. By contrary the strength at break increased because
of lower amount of stress concentration points produced by small calcite
particles.The weakness in the structure of PVAc composite caused by
discontinuity is increased with large calcite particles. Dewetting
mechanism of composite deformation become in this case the dominating one.
Keywords: Poly(vinyl acetate)PVAC Composite filled with Calcite,morphology of Calcite,rheology of PVAC adhesive composites,mechanical properties of film
- Type of paper
: Paper in journal
Title: Thermally Stimullated Oxydative Degradation of High Impact
Polystyrene with Nitric Acid
- Authors:
- Hace, Drago (15006)
- Kovačević, Vera (74041)
- Pajc, Davorka
Journal: Polym.Eng.Sci.
ISSN: 0032-3880
Volume: 35
Year: 1995
Number of references: 31
Language: engleski
Summary: Processes of thermo-chemical degradation and transformation
of high impact polystyrene (HIPS) and influences of concentrated nitric
acid were investigated by various temperature and time. Pure polystyrene
and polybutadiene exposed under the same conditions were comparativelly
investigated. The mechanisms of simultaneous and/or preferable path of
reactions based on IR,UV and 1H NMR investigations were proposed. After
fractionation of copolymer systems DSC,TGA and DMA, as well as mechanical
and morphological measurements were made. Mechanisms of oxidation and
nitration depend on temperature and lead to the molecular and mechanical
heterogenity.The mechanical properties were lowered as a consequence of
degradation processes caused by nitric acid.
Keywords: High impact polystyrene (HIPS), influence of conc.HNO3, structural and morphological properties, mechanical properties, heterogenity
- Type of paper
: Paper in journal
Title: Application of ISO9000 in Leather and Allied Industry
- Authors:
- Kovačević, Vera (74041)
- Mudri, Irinej (164763)
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 43
Year: 1994
Pages: from 104 to 109
Number of references: 13
Language: hrvatski
Summary: The characteristics analyses of leather processing
industry,specially shoe industry,which need to be applicated to the ISO9000
requests was made.The examples and suggestions for quality assurance in
Croatia were given.
Keywords: Leather and allied industry, ISO9000, specifications in shoe industry
- Type of paper
: Paper in journal
Title: Production of Ecologically Approved Leather I
- Authors:
- Kovačević, Vera (74041)
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 43
Year: 1994
Pages: from 9 to 10
Number of references: 6
Language: hrvatski
Summary: Ecological requests demand the adaptation of leather
processing industry.The analysis of possible problems and their solution
allow the production of ecologically aproved leather.In the paper the
processes and acceptable chemicals for such production are given.
Keywords: Ecologically approved leather,new processes and chemicals
- Type of paper
: Paper in journal
Title: Possibilities of use the Leather Wastes without Ecological
Dangerous Products
- Authors:
- Kovačević, Vera (74041)
- Babić, Rudi
Journal: Koža i obuća
Number: 5/6
ISSN: 0450-8726
Volume: 43
Year: 1994
Pages: from 55 to 59
Number of references: 4
Language: hrvatski
Summary: The possibilities of use the leather wastes depend on
production processes and nontoxical chemicals.In paper were given the
results which lead to the aim and are economically and ecologically
approved.
Keywords: Leather wastes,application possibilities
- Type of paper
: Paper in journal
Title: Applications of 2D and 3D CAD/CAM System in Shoe
Industry-Promises and Rality
- Authors:
- Tucaković-Mujagić, Ljiljana (69102)
- Kovačević, Vera (74041)
Journal: Koža i obuća
ISSN: 0450-8726
Volume: 43
Year: 1994
Pages: from 81 to 85
Number of references: 6
Language: hrvatski
Summary: In the paper the experiences an 2D and 3D CAD/CAM
application in shoe industry were given.The results stressed the importance
of common last CAD/CAM data base which is the basis of quality assurance
system in shoe industry.
- Type of paper
: Paper in journal
Title: Eksperimental evaluation of the microwave drying of
leather
- Authors:
- Skansi, D
- Bajza, Željko (140705)
- Arapović, A
Journal: JSLTC
ISSN: 0144-0322
Volume: 79
Year: 1995
Language: engleski
Summary: The microwave drying of industrially prepared leather has
been experimentally investigated on a laboratory scale. The experiments
were performed at three different levels of microwave heating power.
Measuring the mass of the sample through the drying duration, the kinetic
drying curves were obtained. For correlation of experimental results the
exponential model and its differential form has been applied. Results
obtained show a high level of correlation and a strong relationship between
applied microwave power and drying time(rate), type of leather sample and
their pretreatment (vacuum and sidewise dewatering).
Keywords: Drying, kinetics, leather, microwave heating.
- Type of paper
: Paper in journal
Title: Die fahigkeit der olbindung auf das leder
- Authors:
- Bajza, Željko (140705)
- Sugnetić, N
Journal: Leder und Hautemarkt
Number: 9
ISSN: 4477-D
Volume: 46
Year: 1994
Pages: from 30 to 32
Number of references: 19
Language: njemački
Summary: Leather was fatliquored with various types of fatliquor
commonly used.Three of them based on sperm oil, three on fish oil, and
three on natlons of these natural oils. In each group, one fatliquor was
sulphonated (aulphited), the second fatliquor was sulphated, and the third
contained an addition of an emulsifier. For all leather samples produced,
the amounts of fixed and non-fixed fats (and the moist-content) were
determined. All fatliquors were analyzed to determinate the fat content and
the amounts of sulphonated and sulphated, end the degree of sulphonation
(sulphatization) was also determined. The results should indicate the
fixation capacity of the various types of fatliquor on the leather and also
provide information on the fixation as a function of the degree of
sulphonation and on the amount of the sulphited components.
Keywords: Fat-liquoring, hide, leather, phisic-mechanical properties, stress, strain, tanning, leather processing.
- Type of paper
: Paper in journal
Title: Preparing of standards for the complex evaluation of the
quality of leather (usage of ISO9000 in leatrher industry)
- Authors:
- Bajza, Željko (140705)
Journal: Koža i obuća
Number: 3/4
ISSN: 0450-8726
Volume: 43
Year: 1994
Pages: from 31 to 36
Language: hrvatski
Summary: The author in the beginning of the article gives the
description of the different europeans standards for the leather industry.
After that he describes the new system of normisation and certification in
the leather industry.
Keywords: Quality of leather, european standards
- Type of paper
: Paper in journal
Title: Developping processes in the leather manufacturing
- Authors:
- Bajza, Željko (140705)
Journal: Koža i obuća
Number: 3/4
ISSN: 0450-8726
Volume: 43
Year: 1994
Pages: from 39 to 40
Language: hrvatski
Summary: In the article are described the newest trends in the
leather processing technologie. There are described the operations of the
soaking with the enzymes, fleshing after soaking, liming with new
chemicals, deliming with carbon dioxid, tanning with smaller quantities of
chrome and alternatives tannages without chrome. For retanning, dying and
fatliquoring are given new methods. In the finishing department the most
important is the usage of the finishes on the water base.
Keywords: Leather manufacturing, new trends in leather processing, new chemicals
- Type of paper
: Paper in journal
Title: The investigation of tuning activity on ecological aspects
of the leather production
- Authors:
- Bajza, Željko (140705)
- Bravar, Mladen (5281)
Journal: Koža i obuća
Number: 7/8
ISSN: 0450-8726
Volume: 44
Year: 1995
Language: hrvatski
Summary: Newer research in the field of the possibility of the use
of different tanning agents appears important from the standpoints of
economy and ecology. Chrome, as well as glutaraldehyde tannings on cow
25-30 kg salt raw hides were made and the obtained leathers were tcsted in
view of their physico-mechnical, thermal and chemical characteristics. At
some stages of leather processing there were some appropriate test made,
such as cyclic stress-strain, and DSC also, wastewater parameters were
followed. The comparisons between various leathers were tried to be
presented.
Keywords: Tuning, ecological aspect, leather production
- Type of paper
: Paper in proceedings
Title: New testing and evaluating method of toepuffs
- Authors:
- Ažman, J
- Dolžan, V
- Kovačević, Vera (74041)
Proceedings title: 10th International Shoemaking Symposium-Techobuv 91
Language: engleski
Place: Zlin, čehoslovačka
Year: 1991
Pages: from 56 to 62
Meeting: International Symposium "Chemshoe 91"
Held: from 11/11/91 to 11/14/91
Summary: The authors describe and evidence the procedure of testing
toepuffs where such force is being measured which causes the depthof
protruding of 5mm using a half-ball tool where the remainingdeformation
after several loadings and unloadings ismeasured.According to the described
method it is possible toprecisely determine the parameters of the quality
of the toe puffmaterial which are of the utmost importance for the
shoeindustry.The method has a high degree of reproducibility andgives a
precise idea on the possibilities of the given toe puffmaterial.There is a
detailed description of the testing device onwhich tests are being done,the
preparation of the test sample isdescribed and the results of testing using
diagrams andmathematical computations are evaluated.
Keywords: shoe,testing,toepuffs
- Type of paper
: Paper in proceedings
Title: Leather micromehanics
- Authors:
- Bajza, Željko (140705)
- Vuković, Tomica (78506)
- Agić, Ante (137300)
Proceedings title: Compendium of advanced topics on leather technology
Language: engleski
Place: Barcelona, Španjolska
Year: 1991
Pages: from 1141 to 1149
Meeting: XXI Congress of I.U.L.T.C.S.
Held: from 09/11/91 to 09/13/91
Summary: In view of mechanics leather is consisted of collagen
fibers andelastin with addition of fats,water and
inorganicmaterials.Uniform pore reducing in the direction of the facegives
leather directed permeability.The complex nature ofdeformation
kinematics(theory of large deformations)andcomplex space geometrical form
of leather products result ininsufficient theoretical studying of leather
mechanics.Theauthors have made physical investigations of
stretching,tensilestrength and tearing.Model which have to explain
phenomena ofleather firmness on physical mechanical grounds is
made.Lanirsmodel of biological tissue behaviour is made and relation
betweendeformation and tighteningis showed in extendingdiagram.Mechanism of
diffusion of wapour,sweat and air ispresented as well as free energy
increase calculated byFlory-Huggins equation.It is concluded that
application ofmicromechanics and scientific criteria can contribute
tounderstanding of many phenomena in production and using ofnatural
leather.
Keywords: leather micromehanics,theoretical Lanir-s model,mechanical properties
- Type of paper
: Paper in proceedings
Title: Effect of Polymer-Filler Adhesion on the Film Properties
of Poly(vinyl-acetate) Adhesives Filled with Calcite Fillers
- Authors:
- Kovačević, Vera (74041)
- Lučić, Sanja
- Hace, Drago (15006)
Proceedings title: 13.dani Društva plastičara i gumaraca
Language: hrvatski
Place: Zagreb
Year: 1995
Pages: from 87 to 94
Meeting: 13.dani Društva plastičara i gumaraca
Held: from 09/26/95 to 09/29/95
Summary: The mechanical properties of film adhesives depend very
strong on the degree of interfacial bond developed between
poly(vinyl-acetate) polymer matrix and calcite filler. In the present paper
tensile properties were evaluated in the composition range 0-15 wt %
calcite, along with filler surface
modifications with stearic acid. State of dispersion of the filler in the
polymer matrix has been analyzed by studying the morphology of the adhesive
films with the help of scanning electron microscopy. Tensile strength
increased with filler concentration, while breaking elongation decreased.
The tensile increase was attributed to the increase of adhesion between
polymer and filler. Generation of discontinuity in adhesive film structure
through formation of stress
concentration points accounted for breaking elongation decrease and
relative tensile strength decrease, when very coarse filler particles were
present. The tensile breaking strength data were analysed using some models
in orther to understand the generation of discontinuity or weakness in the
structure of two-phase adhesive films. Breaking elongation improvement of
adhesive films depend on the effectiveness of the coupling agent in the
optimisation work of adhesion, wetting ability of the poly(vinyl-acetate)
and, as a result, lowering the free surface energy of the interface.
Keywords: Poly(vinyl acetate)PVAC adhesive, composite PVAC matrix/CaCO3 filler, adhesion, mechanical properties of film
- Type of paper
: Paper in proceedings
Title: Investigation of Adhesives and Adhesive Bonds Properties
in Degradation Conditions
- Authors:
- Kovačević, Vera (74041)
- Lučić, Sanja
- Hace, Drago (15006)
- Cerovečki, Željko
Proceedings title: Od uzorka do podataka i informacija
Language: hrvatski
Place: Zagreb
Year: 1995
Meeting: Od uzorka do podataka i informacija
Summary: In the paper an overview of investigations of adhesive
systems based on PUR,CR and PVAC were given.The results showed that
adhesive composition and separate components had significant influence on
adhesive properties and quality characteristics.
Keywords: Adhesives,composition and components,adhesive quality
Other: ...u tisku.
- Type of paper
: Paper in proceedings
Title: Changes physical and mechanical properties of leather in
process of manufacturing
- Authors:
- Bajza, Željko (140705)
- Agić, Ante (137300)
- Sugnetić, N
Proceedings title: International congress on the leather, shoe and allied industries
Language: engleski
Place: Budapest, Mađarska
Year: 1994
Pages: from 1 to 11
Meeting: International Congress on the Leather, Shoe and Allied Industries
Held: from 10/12/94 to 10/14/94
Summary: This study presents the results of testing of the physical
and mechanical properties of leather
;amples tanned in different ways. Pieces of cowhide and pigskin were used
as basic samples.
Testing was performed in order to examine the deformation and stress of the
samples.
Etensibility of the pigskin samples was tested with preliminary
pre-stress. Stress and
deformation tests on dried samples were performed on the Zwick machine.
The opening theoretical part of the study contains mathematical
description of Hook's
law for plane stress. The composite model for a complex module was
described in the case
nhen both components had a high level of elasticity. Hook's law cannot be
applied for larger
deformations, therefore, the energy of elastic deformation was presented as
a function of
deformation and relative porousness. Experimental results showed that the
changes in
mechanical properties depend on the substance used in leather processing as
well as on the
pre-stress and extension in different directions.
Keywords: Collagen, Deformation, electronic microscopy, fat liquoring, hide, leather, morphology, stress, tanning
- Type of paper
: Paper in proceedings
Title: Influence of different types of tannages on quality and
ecological friendly leather
- Authors:
- Bajza, Željko (140705)
- Bravar, Mladen (5281)
- Agić, Ante (137300)
Proceedings title: XXIII IULTCS Congress
Language: engleski
Place: Friedrichshafen, Njemačka
Year: 1995
Pages: from 1 to 18
Meeting: XXIII I.U.L.T.C.S.
Summary: I
DIFERENT TYPES OF ENVIRONMENTALLY FRIENDLY LEAER TANNINGS
Newer research in the field of the possibility of the use of
different
tanning agents appears important from the standpoints of economy
and
ecology. Chrome, as weil as glutaraldehyde tannings on cow 25-30
kg
salt raw hides were made and the obtained leathers were tested in
view
of their physico- mechnical, thermal and chemical characteristics.
At some
stages of leather processing there were some appropiate test made,
such
as cyclic stress- strain, and DSC also, waste- water
parameters were
followed.
The comparisons between various leathers were tried to be
presented.
Keywords: Environmentally friendly leather, tanning, mechanical and thermal properties
- Type of paper
: Paper in proceedings
Title: The running shoe as a shock absorber
- Authors:
- Agić, Ante (137300)
Proceedings title: 10th International Symposium on Biomedical Engineering 94
Language: engleski
Place: Zagreb
Year: 1994
Pages: from 79 to 82
Meeting: 10th International Symposium on Biomedical Engineering 94
Held: from 11/24/94 to 11/26/94
Summary: Many injure in running have related to insuficient
shock-absorption properties of the shoes. A critical test for shoes is how
well they absorb the shock and transmit the force through the body. The aim
of this study was to develop a mathematical tool that could explain the
shock isolation
phenomena in athletic shoes. The idealized shock isolation system has
considered to have composed of a rigid mass (human body) supported on a
rigid foundation by a single isolator (athletic shoe) undergoing
unidirectional dynamic motion. Linear stiffens element in parallel with a
pneumatic damping element has used to characterize the isolator. Shock
excitation has defined in terms of cosine pulse displacement upon a
foundation. The residual shock amplifccation curves for displacement and
acceleration for isolation system in terms of the relative values of the
shock pulse time duration and the isolation system natural period has
presented.
Keywords: Running shoe, shock isolation, pneumatic damping
- Type of paper
: Paper in proceedings
Title: System for shoe designing
- Authors:
- Agić, Ante (137300)
Proceedings title: Informacijski sustavi 95
Language: hrvatski
Place: Varaždin
Year: 1995
Pages: from B7 to 13
Meeting: Informacijski sustavi 95
Summary: Shue design and construction with computer is undoubtly
important segment of modern shue production.Information systems in shue
industry is very complex and needs special attention. In this work the
above mentioned system which is installed on the Faculty of chemical
engineering and technology in Zagreb will be presented. Hierarchy in
threedimensional shoe modelling and constructing lie on last definition for
special type of shoe. Ergonomical and biomechanical standards of shue
projecting(anatomic shape, grading, last shape, age, environment,...) are a
part of system data base. Complex geometric shape of the shue demand
application of surface graphics with digitalisation.Shue upper construction
have to satisfy comfortability criteria(strength evaluation,heat-diffusion
protection).Shue bottom construction have to provide shock isolation.
Special technologies with NC machines will assure high level of modular
automation and flexible shoe production.
Keywords: CAD-CAM, comfortability, shoe, biomechanics
- Type of paper
: Summary in proceedings
Title: Structural changes of leather in process of manufacturing
measured by Fourier-transform infrared spectroscopy
- Authors:
- Bajza, Željko (140705)
- Posarić, J
Proceedings title: Euroanalysis VIII
Language: engleski
Place: Edinburgh, Engleska
Year: 1993
Pages: from 1 to 7
Meeting: European Conference on Analytical Chemistry
Held: from 09/05/93 to 09/11/93
Summary: During the process of tanning and manufacturing,a raw
hidechanges its properities and chemical structure.Changes ofchemical
structure,related to remove some components ofbiotissues,like globular
proteins,fats or serum and adding ofbonding of auxiliaries
liketannages,fat-liquors,limings,finishers,ect.,could be analysedusing
different analytical techniques and methods.One of the mostpowerful
techniques is the structural analysis of complexmaterials,infrared
spectroscopy(IR),has been used in leatherresearch for many
years.Developments made in the field ofmeasurement of reflected light and
it introduction of fastFourier transform(FT) techniques have established
new methods andtheir applications have been described recently.In the work
thestructural behaviour of leather during the
manufacturingprocess,step-by-step ,was of special interest.Samples
preparedunder normal conditions of manufacturing process were analysedunder
measurements of attenuated total reflectance(ATR) onFourier transform
infrared(FTIR) spectrophotometer.The FTIRspectra show a very complex
pattern of signals related to thechemical structure of additives and of
leather .Computeddifferential spectra analysis was used to solve
structuralproblems caused by the complex structure of leather's
naturalmatrix.A very large area of use of both techniques was found inthe
field of analysis and quality control in tanning processes.
Keywords: spectroscopic analysis of leather,ATR and FTIR techniques,complex structure of natural leather and additives
- Type of paper
: Ph.D.
Title: Dependence of the Process of Mechanical Deformation of
Hide Samples on their Structure and Processing
Faculty: Fakultet kemijskog inženjerstva i tehnologije Zagreb
Author: BAJZA ŽELJKO
Date of defense: 06/27/94
Language: hrvatski
Number of pages: 153
Summary: This study observes changes in physic-mechanical and
chemical properties of hide samples in the course of liming, tanning,
neutralization, retanning, dying, fat-liquoring and finishing.The study
estabilished the interdependence of mechanical deforcnation and structures
of samples as well as the influence of the processing conditions on the
structure and deformations of hide.
Depending on the direction of texture spreading, a number of experimental
techniques of hide characterizaton was applied.To investigate
physic-mechanical properties the results of the stress and deformation
experiments were used. In additon, the experiments of wedge cutting as
well as those of relaxation and hysteresis were performed. After passing
through different processing stages, the samples were tested by Fourier -
transform infrared as well as by electronic microscopy.The experimental
results have shown that processing causes substantial changes in the
properties of hide. Globular proteins, fat, and other intertextural
substances are extracted. Hide absorbs substances used in processing.In the
course of processing the fiber diameter decreases while porosity increases.
Also, the spreading of fibers and the texture become more coherent.This
study observes changes in physic-mechanical and chemical properties of hide
samples in the course of liming, tanning, neutralization, retanning, dying,
fat-liquoring and finishing.The study estabilished the interdependence of
mechanical deformation and structures of samples as well as the influence
of the processing conditions on the structure and deformations of
hide.Depending on the direction of texture spreading, a number of
experimental techniques of hide characterizaton was applied. To investigate
physic-mechanical properties the results of the stress and deformation
experiments were used. In
additon, the experiments of wedge cutting as well as those of relaxation
and hysteresis were performed. After passing through different processing
stages, the samples were tested by Fourier - transfonn infrared as well as
by electronic
microscopy.The experimental results have shown that processing causes
substantial changes in the properties of hide. Globular proteins, fat, and
other intertextural substances are extracted. Hide absorbs substances used
in processing. In the course of processing the fiber diameter decreases
while porosity increases. Also,the spreading of fibers and the texture
become more coherent.
Keywords: Collagen, deformation, electronic microscopy, fat liquoring, hide, infrared spectroscopy, leather, morphology of hide, phisic-mechanical properties, stress, tanning and leather processing
- Type of paper
: Survey/Study
Title: Development and application of new types of auxiliary
products for white leather manufacturing
- Authors:
- Kovačević, Vera (74041)
- Mladinić, Biserka (182041)
- Morović, Ljiljana (197725)
Ordering party: Kutrilin
Institution depot: Fakultet kemijskog inženjerstva i tehnologije
Year: 1993
Number of pages: 22
Language: hrvatski
Summary: In the final study based on literature and situation in
auxiliaryagents production for leather manufacturing in and out
ofCroatia,the research trend of developing were suggested speciallyfor
light leather products.As a result of experimental work thenew auxiliary
products were developed.
Keywords: trends of researching and developing of auxiliary products for leather manufacturing,new products
- Type of paper
: Survey/Study
Title: Quality product assurance of polyurethane adhesive
Termofix
- Authors:
- Kovačević, Vera (74041)
Ordering party: Chromos-tvornica sintetskih smola
Institution depot: Fakultet kemijskog inženjerstva i tehnologije
Year: 1994
Number of pages: 12
Language: hrvatski
Summary: In this study the quality caharacteristics of new product
Termofix adhesive used in shoe and allied industry were defined based on
literature references and quality assurance needs in ISO9000 series.The
investigation methodology were also defined.The conclusions about the
product quality which could serve the producer as market references as well
as the part in quality assurance system in enterprise were drawn.
Keywords: Product quality assurance,adhesive Termofix based on PUR,new product
- Type of paper
: Technical report
Title: Mechanical characteristics of special leather samples
- Authors:
- Kovačević, Vera (74041)
Ordering party: Medicinski fakultet
Institution depot: Fakultet kemijskog inženjerstva i tehnologije
Year: 1992
Number of pages: 20
Language: hrvatski
Summary: Complex structure of skins could cause specific
mechanicalbehaviour which is of interest for investigations.The
specialsamples of skin samples prepared with medical substances withthe aim
of examination of wound effect were studied.Theconclusion about mechanical
properties of raw biomaterial andabout effects of special medical treatment
were drawn.
Keywords: skin,mechanical behaviour,medical treatment of wounded skin
- Type of paper
: Technical report
Title: Model engineering and grading using CAD/CAM system
- Authors:
- Kovačević, Vera (74041)
- Tucaković-Mujagić, Ljiljana (69102)
Ordering party: DIOZ
Institution depot: Fakultet kemijskog inženjerstva i tehnologije
Year: 1993
Number of pages: 12
Language: hrvatski
Summary: Application of CAD/CAM system in Croatian shoe
enterprisessupposed in this moment edducation of technical staff
andrealisation of detailed engineering of selected models.In thisway the
model files for each enterprise could assure the work ontheir own system in
the future,what is necessary for successfullinking in the word production.
Keywords: CAD/CAM system in Croatian shoe factories,engineering of selected models
- Type of paper
: Technical report
Title: Investigation of soles cementing
- Authors:
- Kovačević, Vera (74041)
Ordering party: ZAGREB
Institution depot: Fakultet kemijskog inženjerstva i tehnologije
Year: 1994
Number of pages: 5
Language: hrvatski
Summary: Weak points at glued shoes are soles joint strength.From
thisreason it is necessary to make the investigations on specialprepared
finished shoe,which in correlation with others allow theconclusions about
shoe quality,selection of materials andadhesives and also about adequate
cementing process.
Keywords: shue soles cementing,methods of finished shue investigation
- Type of paper
: Technical report
Title: Aplication of adhesives for military program
- Authors:
- Kovačević, Vera (74041)
Ordering party: GIB
Institution depot: Fakultet kemijskog inženjerstva i tehnologije
Year: 1993
Number of pages: 7
Language: hrvatski
Summary: Quality assurance of glued shoes in required programs
asmilitary,demands the precious defining of elements which couldinfluence
on results.In this case the adhesives according specialapplications were
examined.
Keywords: quality assurance of glued shues,adhesives for special aplications
- Type of paper
: Technical report
Title: Investigations of adhesive joint strength
- Authors:
- Kovačević, Vera (74041)
Ordering party: Borovo
Institution depot: Fakultet kemijskog inženjerstva i tehnologije
Year: 1992
Number of pages: 20
Language: hrvatski
Summary: Adhesive joint strength depends on many factors which have
to beinvestigated like selection of materials,adhesives,surfacepreparing
and enviromental influence.The investigations withvarious materials and
adhesives were provided and the conclusionsabout the quality of adhesive
joints and the causes joint failurewere made.
Keywords: adhesive joint,adhesive joint failure
- Type of paper
: Technical report
Title: Analysis of hydrofobic leather
- Authors:
- Kovačević, Vera (74041)
Ordering party: Inkop
Institution depot: Fakultet kemijskog inženjerstva i tehnologije
Year: 1993
Number of pages: 19
Language: hrvatski
Summary: Investigations of hidrofobic properities of leather
speciallywaterproofness but with remained gas permeability,water vapourand
air,were made both for suppliers and producers of materialsand finished
products.The goal of investigations were alsopreparing for system quality
assurance in the near future.
Keywords: hydrofobic properties of leather,waterproofness,gas permeability,quality assurance
- Type of paper
: Technical report
Title: Investigation of shue for special application
- Authors:
- Kovačević, Vera (74041)
- Tucaković-Mujagić, Ljiljana (69102)
Ordering party: Ministarstvo unutarnjih poslova Republike Hrvatske
Institution depot: Fakultet kemijskog inženjerstva i tehnologije
Year: 1993
Number of pages: 14
Language: hrvatski
Summary: Defining of shue quality depend on
assignment,specialrequirements,type,model,ways of parts connecting and
establishedcharacteristics of materials.In agreement with supplier
andpurchaser the way of establishing and quality control wassuggested with
purpose to become a part of quality assurancesystem along with european
standards.
Keywords: shue quality assurance
- Type of paper
: Technical report
Title: Investigation of materials and shue making quality
- Authors:
- Kovačević, Vera (74041)
- Tucaković-Mujagić, Ljiljana (69102)
Ordering party: Ministarstvo unutarnjih poslova Republike Hrvatske
Institution depot: Fakultet kemijskog inženjerstva i tehnologije
Year: 1993
Number of pages: 8
Language: hrvatski
Summary: Shues for special application require more attention when
thequality of materials and manufacturing are in qustion.In presentlack of
national standards the way of quality controlfor selected model was
suggested in consultation with adequateforeign standards.
Keywords: shue quality,characteristics of shue materials,standards
- Type of paper
: New product
Title: Kutrifob SMH plus-product for leather hydrofobing and
fatting
- Authors:
- Mladinić, Biserka (182041)
- Morović, Ljiljana (197725)
- Kovačević, Vera (74041)
Approved by institution: Kutrilin
Institution depot: Kutrilin
Language: hrvatski
Summary: New product for fatting and hydrofobing of leather suitable
alsofor light leather with examined and recomended procedure ofapplication
in various leather types manufacturing.
Keywords: product for hydrofobing and fatting of leather,recommended procedure
- Type of paper
: New product
Title: Kutrilix WWL-product for leather fatting
- Authors:
- Mladinić, Biserka (182041)
- Morović, Ljiljana (197725)
- Kovačević, Vera (74041)
Approved by institution: Kutrilin
Institution depot: Kutrilin
Language: hrvatski
Summary: New product for fatting based on optimal composition of
surfaceactive components,softing agents and natural triglicerides
wasinvestigated for various types of leather specially white leatherwith
recomended procedure.
Keywords: product for fatting of various types of leather,recommended procedure
- Type of paper
: New product
Title: Kutritan 5-product for leather neutralisation and
aftertanning
- Authors:
- Morović, Ljiljana (197725)
- Mladinić, Biserka (182041)
Approved by institution: Kutrilin
Institution depot: Kutrilin
Language: hrvatski
Summary: Product based on ligninsulfonic acid for neutralisation
andaftertanning of chromiumtanned leather was improved as a resultof
investigations.
Keywords: improved product for neutralisation and aftertanning of chromiumtanned leather,product based on ligninsulphonic acid
- Type of paper
: New product
Title: Kutripol LI-product for leather and fur fatting
- Authors:
- Morović, Ljiljana (197725)
- Mladinić, Biserka (182041)
Approved by institution: Kutrilin
Institution depot: Kutrilin
Language: hrvatski
Summary: New optimal composition based on sulphated and sulphited
naturaloil,softener and complex activated emulgators was done.Results
ofinvestigations showed very good effects on soft leather.
Keywords: prototype product,product for leather and fur fatting,effect of softness
- Type of paper
: Invited lecture
Title: Thermochemical Degradation of
Poly(butadiene-1,4-g-styrene)Fractionated Parts
Institution: University of North Texas
Year: 1995
- Type of paper
: Invited lecture
Title: Investigation of Composite Properties of Poly(vinyl
acetate)Based Polymers
Institution: University of North Texas
Year: 1995
- Type of paper
: Invited lecture
Title: Effect of Polymer-Filler Adhesion on the Film Properties
of Poly(vinyl acetate) Adhesives
Institution: Društvo plastičara i gumaraca
Year: 1995
