Synthesis and properties of chitosan-modified poly(vinyl acetate)
β Scribed by Trong-Ming Don; Chia-Fong King; Wen-Yen Chiu
- Publisher
- John Wiley and Sons
- Year
- 2002
- Tongue
- English
- Weight
- 126 KB
- Volume
- 86
- Category
- Article
- ISSN
- 0021-8995
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
A redox initiator, cerium ammonium nitrate, was used to initiate the graft copolymerization of vinyl acetate (VAc) onto the chitosan chain in a dispersion polymerization at 60Β°C. With an addition of 0.5β7.5 g of chitosan based on 50 g of VAc, the monomer conversion was found to be between 70 and 80% after 2 h of reaction. The grafting efficiency increased with the amount of chitosan added; yet, the grafting ratio increased slightly and then decreased. After the reaction, a stable dispersion system was observed and the surface of the latex particles was found to be rich in chitosan. All the experimental results indicated that the chitosan molecules not only took part in the graft copolymerization, but also served as a surfactant, providing the stability of the dispersion particles. If the dispersion aqueous solution was ovenβdried, a particulate membrane was formed. The experimental results indicated that the incorporation of poly(vinyl acetate) to the chitosan chains increased the toughness and decreased the water absorption of the chitosan material. Β© 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3057β3063, 2002
π SIMILAR VOLUMES
## Abstract Potassium persulfate (K~2~S~2~O~8~) was used to initiate the polymerization of acrylic acid (AA) monomer in a chitosan (CS) solution. Both a poly(acrylic acid) (PAA) homopolymer and a CSβ__co__βPAA copolymer were produced. When the amount of AA was increased from 5 to 40 g with 5 g of C
Poly(viny1 acetate peroxide) (PVACP) was prepared from vinyl acetate by free-radicalinitiated oxidative polymerization. The polyperoxide was isolated and characterized by different spectroscopic methods. The extreme instability of PVACP was demonstrated by FTIR spectroscopy. The 'Hand I3C-NMR studie
A series of hydrophobically modified water-soluble poly(vinyl alcohol) (PVA) polymers was prepared by grafting urethanized PVA with varying fractions of fatty acid chlorides of various chain lengths. The objective of the synthesis was to prepare polymers that can be applied to enhanced oil recovery.
## Abstract The use of weak alkalies such as sodium carbonate (Na~2~CO~3~), sodium bicarbonate (NaHCO~3~) and their 1 : 1 molar mixture, and strong alkalies such as sodium hydroxide (NaOH) and sodium methoxide (NaOMe) as pH controllers in suspension polymerization of vinyl acetate monomer (VAM) has