scholarly journals The effect of ethylene content on the interaction between ethylene-vinyl alcohol copolymers and water—II: Influence of water sorption on the mechanical properties of EVOH copolymers

2006 ◽  
Vol 25 (7) ◽  
pp. 860-867 ◽  
Author(s):  
Lluís Cabedo ◽  
José M. Lagarón ◽  
David Cava ◽  
Juan J. Saura ◽  
Enrique Giménez
Keyword(s):  
Mechanical Properties ◽  
Vinyl Alcohol ◽  
Water Sorption ◽  
Ethylene Vinyl Alcohol ◽  
Ethylene Content ◽  
Influence Of Water

Mechanical properties of a laminin–apatite composite layer formed on an ethylene–vinyl alcohol copolymer

2009 ◽  
Vol 29 (5) ◽  
pp. 1681-1686 ◽  
Author(s):  
Ayako Oyane ◽  
Yoshiro Yokoyama ◽  
Mayumi Kasahara ◽  
Noboru Ichinose ◽  
Makoto Saito ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Vinyl Alcohol ◽  
Composite Layer ◽  
Ethylene Vinyl Alcohol ◽  
Ethylene Vinyl Alcohol Copolymer

scholarly journals Design of Novel PLA/OMMT Films with Improved Gas Barrier and Mechanical Properties by Intercalating OMMT Interlayer with High Gas Barrier Polymers

Polymers ◽  
2021 ◽  
Vol 13 (22) ◽  
pp. 3962
Author(s):  
Abdul Shakoor Shar ◽  
Caili Zhang ◽  
Xieqing Song ◽  
Yunxuan Weng ◽  
Qiuyue Du
Keyword(s):  
Mechanical Properties ◽  
Vinyl Alcohol ◽  
Composite Films ◽  
Barrier Properties ◽  
Poly Vinyl Alcohol ◽  
Diffraction Measurement ◽  
Scanning Calorimetry ◽  
Gas Barrier ◽  
Ethylene Vinyl Alcohol ◽  
Barrier Polymers

Polymer/clay composites are an innovative class of materials. In this study, we present a facile method for the preparation of biodegradable and robust PLA/organomodified montmorillonite (OMMT) composite films with excellent gas barrier performance. When the design of PLA/OMMT composite films, in addition to making OMMT have good intercalation effect in the matrix, the compatibility of intercalating polymer and matrix should also be considered. In this work, two polymers with high gas barrier properties, namely poly(vinyl alcohol) (PVA) and ethylene vinyl alcohol copolymer (EVOH), were selected to intercalate OMMT. The morphology and microstructures of the prepared PLA/PVA/OMMT and PLA/EVOH/OMMT composites were characterized by the X-ray diffraction measurement, scanning electron microscopy, and differential scanning calorimetry. It was shown that the good dispersibility of PVA in the PLA matrix, rather than the intercalation effect, was responsible for the improved gas barrier and mechanical properties of PLA/PVA/OMMT composite. The elongation at break increases from 4.5% to 22.7% when 1 wt % PVA is added to PLA/OMMT. Moreover, gas barrier of PLA/PVA1/OMMT measured as O2 permeability is 52.8% higher than that of neat PLA. This work provides a route to intercalate OMMT interlayer with high gas barrier polymers and thus can be a useful reference to fabricate PLA/OMMT composites with improved gas barrier and mechanical properties. A comparison of oxygen permeabilities with existing commercial packaging films indicates that the biodegradable PLA/PVA/OMMT may serve as a viable substitute for packaging film applications.

Influence of water sorption on mechanical properties of injection-molded thermoplastic denture base resins

2014 ◽  
Vol 72 (8) ◽  
pp. 859-865 ◽  
Author(s):  
Ippei Hamanaka ◽  
Misa Iwamoto ◽  
Lippo Lassila ◽  
Pekka Vallittu ◽  
Hiroshi Shimizu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Water Sorption ◽  
Denture Base ◽  
Influence Of Water ◽  
Injection Molded

A study of ethylene vinyl alcohol copolymer fiber for the drawing process

2016 ◽  
Vol 87 (9) ◽  
pp. 1081-1095
Author(s):  
Syang-Peng Rwei ◽  
Zhi-Feng Jue ◽  
Whe-Yi Chiang ◽  
Yu-Hua Chen ◽  
Jui-Hsiang Chen
Keyword(s):  
Stress Relaxation ◽  
Initial Stress ◽  
Vinyl Alcohol ◽  
Draw Ratio ◽  
Drawing Process ◽  
Ethylene Vinyl Alcohol ◽  
Drawing Temperature ◽  
Drawing Stress ◽  
Initial Modulus ◽  
Ethylene Content

This study investigates the effect of the drawing process of ethylene vinyl alcohol (EVOH) fibers on their physical properties. Three different ethylene contents, namely EV-32, EV-38 and EV-44, were used where the ethylene content has the order of EV-44 > EV-38 > EV-32. The result indicates that at the same drawing temperature and draw ratio, the online drawing stress of the fiber with high ethylene content is higher than that with low ethylene content. Moreover, the drawn EVOH fiber, at the drawing temperature of 80℃ and the draw ratio of 2.0, exhibits an optimal mechanical property. As the draw ratio increases, the online drawing stress, birefringence and initial modulus increase. Notably, unlike typical polymeric fibers, the glass transition temperature ( Tg) of the drawn EVOH fibers decreases with the draw ratio due to more water being absorbed by thinner fibers within the same number of samples. The draw ratio was found to have little effect on the melting temperature ( Tm). At the same draw ratio, the online drawing stress, birefringence, stress and initial modulus of the fiber EV-44, which has the highest ethylene content, is higher than those of EV-32 and EV-38. The creep strain of the drawn fibers EV-32 and EV-38 linearly increase with the drawing time when the applied stress maintains constant at 150 MPa, while an insignificant increase is observed for EV-44, suggesting that EV-44 is difficult to deform and has higher size stability. In the stress relaxation test, the elongation increases with the initial stress. At the same elongation percentage, the initial stress of the drawn fibers has the following trend: EV-44 > EV-38 > EV-32 and the stress relaxation time (τ) has the following trend: EV-44 > EV-38 > EV-32, indicating again that EV-44 is relatively difficult to deform during drawing. Finally, EV-44 fiber performed the best in the hot water resistance test.

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