Synthesis and Characterization of the Novel Thermoresponsive Conjugates Based on Poly(3-hydroxy alkanoates)
Tugba Toraman, B Hazer
article (Uluslararası, Hakemli) | Yazar(lar): Tugba Toraman, B Hazer | Yıl: 2014 | Dergi/Kurum: JOURNAL OF POLYMERS AND THE ENVIRONMENT | İndeks: WOS.SCI | DOI: 10.1007/s10924-014-0646-y | Anahtar Kelimeler: Poly (3-hydroxy alkanoate)s, Poly (3-hydroxy undecenoate), Soybean oil-polyester, Thermo responsive PHA conjugat
Novel thermoresponsive polymer conjugates based on microbial polyesters and poly-N-isopropyl acryl amide, PNIPAM, have been reported. The unsaturated poly-3-hydroxy alkanoates, poly (3-hydroxy undecenoate), PHU, and 1:1 mixture of 10-undecenoic acid and soy oil acids, PHU-Sy, were brominated by using bromine in the dark, at room temperature. Brominated PHAs were transformed to macro reversible addition-fragmentation chain transfer (RAFT) agents via the substitution reaction with potassium ethyl xanthate. RAFT polymerization of N-isopropyl acryl amide, NIPAM, was initiated by the PHA-derivative containing xanthate pendant groups in order to obtain brush type PHA-g-PNIPAM thermo responsive amphiphilic graft copolymers. The water uptake of the PHU-g-PNIPAM and PHU-Sy-g-PNIPAM amphiphilic graft copolymers changed from 50 % to completely soluble in water. Structural and thermal characterization of the novel conjugates were carried out by using H-1 NMR, GPC, DSC and TGA techniques.