| Creator |
|
|
|
|
|
| Language |
|
| Publisher |
|
|
|
| Date of Available |
|
| Date |
|
| Source Title |
|
| Vol |
|
| Issue |
|
| First Page |
|
| Last Page |
|
| Publication Type |
|
| Access Rights |
|
| Rights |
|
| Abstract |
Poly(propylene carbonate) (PPC), which can be prepared by the alternating copolymerization of propylene oxide (PO) with carbon dioxide (CO₂), has attracted considerable attention due to its biodegrada...bility, biocompatibility, oxygen-barrier property, and ion-conductivity. However, there are some inherent disadvantages, such as its low thermal stability and limited mechanical strength. Therefore, combination of PPC with other polymers has been investigated to improve its properties and develop PPC-based polymer materials. In light of this background, we designed the graft copolymer, cellulose acetate-graft-PPC with a cellulose acetate (CA) main chain and PPC side chains. CA is a high-performance thermoplastic with excellent mechanical strength as well as biodegradability. Therefore, CA-graft-PPC would be endowed with complementary properties derived from both components. The designed graft copolymer was synthesized via a grafting-to approach. First, the PPC with a terminal alkynyl group (PPC–C≡CH) was synthesized by the immortal PO/CO₂ alternating copolymerization using 4-ethynylbenzoic acid as a chain transfer agent (CTA). PPC–C≡CH with number-average molecular weight (Mₙ) of 3,900–36,600 was successfully obtained by changing the monomer and CTA feed ratios. Then, the resulting PPC–C≡CH was grafted onto CA through copper-catalyzed azide–alkyne cycloaddition (CuAAC). The reaction of PPC–C≡CH (Mₙ = 5,600, 7,000, 15,600, or 36,600) with azide-functionalized CA (the degree of substitution of CA by azide groups = 0.156 or 0.248) successfully proceeded with CuBr/Cu as catalysts, affording the desired CA-graft-PPC with the degree of substitution of CA by PPC of 0.149–0.235. The resulting graft copolymers exhibit higher thermal decomposition temperature compared with PPC.show more
|
Export Mendeley
p1267-1278