To enhance the physical properties of syndiotacticity-rich (syndiotactic diad content 63ร4%) ultra-high molecular weight (UHMW) (number-average degree of polymerization 12 300) poly(vinyl alcohol) (PVA) รlm, it was solution blended with rigid-rod imogolite in dimethyl sulphoxide. In addition, the bl
Preparation of syndiotacticity-rich high molecular weight poly(vinyl alcohol)/iodine polarizing film with high water resistance
โ Scribed by Man Ho Han; Won Seok Lyoo
- Publisher
- John Wiley and Sons
- Year
- 2010
- Tongue
- English
- Weight
- 248 KB
- Volume
- 115
- Category
- Article
- ISSN
- 0021-8995
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โฆ Synopsis
Abstract
To enhance durability of poly(vinyl alcohol) (PVA)/iodine polarizing film under humid and warm atmospheres and to identify the effects of syndiotacticity on the polarizing efficiency (PE) and durability of PVA/iodine complex film, we prepared three high molecular weight (PVA)s with similar numberโaverage degree of polymerization (P~n~) of 4000 and with different syndiotactic diad (sโdiad) contents of 53, 56, and 59%, respectively. It was found that syndiotacticity of PVA had a significant influence on the durability of PVA/iodine complex film in warm and humidity conditions (relative humidity of 80% and temperature of 50ยฐC). That is, both desorption of iodine in PVA/iodine film and transmittance of film decreased with increasing syndiotacticity of PVA. In the case of PE, the values of over 99% were obtained at each optimum conditions. The change of PE (durability) of PVA/iodine complex films having P~n~ of 4000 and sโdiad contents of 56 and 59%, respectively, in warm and humidity conditions was almost zero, whereas those of PVA/iodine film with sโdiad content of 53% and with (P~n~)s of 1700 and 4000 were about 60% and 50%, respectively, under same conditions. ยฉ 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
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