The Synthesis of Cellulose-graft-poly (L-lactide) by Ring-opening Polymerization and the Study of Its Degradability

Abstract

Cellulose-graft-poly (L-lactide) (cellulose-g-PLLA) was successfully prepared via ring-opening polymerization (ROP) by using 4-dimethylaminopyridine (DMAP) as an organic catalyst in an ionic liquid 1-allyl-3-methylimidazolium chloride (AmimCl). The structure and morphology of the polymer was characterized by nuclear magnetic resonance (NMR) and transmission electron microscope (TEM). From wide-angle X-ray powder diffraction (WAXD) and degradation test (by acid, alkaline, PBS and enzyme solution), changes in the crystalline structure as a result of degradation was also investigated. The results indicated that materials which have low degree of crystallinity showing higher degradability, however, in acid liquor, enzyme solution, alkaline liquor and PBS system, the degradation rate of the polymer decreased by the above sequence. Moreover, with the further increase of graft degree of this material, its degradation degree decreased.

Degradation of graft polymer and blend based on cellulose and poly(L‐lactide)

“…Based on previous experiments, a typical polymerization procedure was employed as follows. 4% (w/w) MCC/AmimCl solution was first prepared by mechanical stirring at 80°C under nitrogen for 1 h in a dried Schlenk tube; then L‐LA, DMAP were added into the tube and mixed till dissolved, the tube was degassed in vacuum/N 2 in 1 h cycles (three times); finally, the reaction was kept at 90°C under nitrogen with vigorous stirring for 9 h; after cooling to room temperature, the resultant polymer was precipitated with deionized water, and then the polymer was dissolved in toluene to obtain a purified graft polymer.…”

Catalysis as an Enabling Science for Sustainable Polymers

“…Lipase B from Candida antarctica was expressed in Aspergilus niger and immobilized on acrylics beads and is commercialized as Novozym 435. Lipases were shown to degrade PCL, 504−508 PLA, 504,505 PLLA, 509 poly(γ-butyrolactone), 507 PHB, 508,510 poly(butylene succinate adipate), 511 PCL/PBS blend, 511 and poly(propylene carbonate) 508 in PBS at 37 °C, producing mainly short oligomers. The rates of hydrolysis varied tremendously with the microorganisms/tissue the lipase was extracted from and the polymer.…”

“…Lipase B from Candida antarctica was expressed in Aspergilus niger and immobilized on acrylics beads and is commercialized as Novozym 435. Lipases were shown to degrade PCL, − PLA, , PLLA, poly­(γ-butyrolactone), PHB, , poly­(butylene succinate adipate), PCL/PBS blend, and poly­(propylene carbonate) in PBS at 37 °C, producing mainly short oligomers. The rates of hydrolysis varied tremendously with the microorganisms/tissue the lipase was extracted from and the polymer. , Overall PCL degrades the fastest with quantitative depolymerization obtained with Pseudomonas lipase after 4 days in aqueous media, and the addition of PLA or PPC to PCL greatly decreases this rate.…”

以离子液体为介质的纤维素均相衍生化

“…(Cell-g-PLA) [83] 和 醋 酸 纤 维 素 接 枝 聚 乳 酸 (CA-g-PLA) [84] , 具有合适接枝聚乳酸含量和接枝链长度的 共聚物可以熔融加工, 实现了无外加增塑剂条件下 的纤维素基材料的熔融加工. He课题组 [85] 也采用该 方法合成了纤维素接枝聚乳酸, 并考察了其水解和 酶解行为. Wang课题组 [86,87] 以辛酸亚锡为催化剂, 合成了纤维素接枝聚乳酸, 并通过自组装制得了纳 米微球.…”