Studies on Developing Novel Biodegradable Polymeric Materials from Cellulose and Lignocellulosics

C. M. Buchanan和他的同事最近发现，取代度高达2.5的醋酸纤维素在环境中是可降解的，并且生物降解速率受其取代度的影响。此外，醋酸纤维素的生物降解最终建立了一个自然设计的混合微生物培养物来自活性污泥和^<14>C标记的纤维素酯。这些观察加强了生物降解塑料可以从醋酸纤维素引入的想法。现在需要的是增强醋酸纤维素的热塑性，因为没有适当和合理的增塑，醋酸纤维素不能用作塑料。纤维素酯和聚酯的相容性是要研究的主要课题，但是， ...更多信息 本研究的目的是从纤维素酯实现实用的和可生物降解的塑料。在这些背景下，我们也一直在尝试通过使用反应性加工过程从纤维素酯和醚开发生物降解塑料。该方法包括纤维素衍生物或类似物的低酯化，其中保留一些羟基。这导致接枝，即内部塑化。结果表明，当接枝量增加时，起外增塑剂作用的均聚物的渗出量减少。二羧酸酐和单环氧化物或甘油、ε-己内酰胺和单环氧化物在乙酸纤维素存在下在相对高的温度下在一定的扭矩下成功地反应，所有化合物通过该扭矩熔化，产生可生物降解的塑料。在这方面，可以开发一种新的技术，通过该技术可以将化学键合到CA的接枝低聚物与均聚物定量地、完全地分离。在此基础上，探讨了提高接枝率的方法和条件。少

It has been found very recently by C.M.Buchanan and his coworkers that cellulose acetates with the degree of substitution up 2.5 are degradable in the environment and that the rate of biodegradation is influenced by its degree of substitution. Additionally, the biodegradation of cellulose acetates was conclusively established with a naturally devised mixed microbial culture derived from an activated sludge and ^<14>C labeled cellulose esters.These observations have strengthened the idea that biodegradable plastics can be introduced from cellulose acetates. What is needed now is enrichment of thermoplastic properties of the cellulose acetates, since, without proper and reasonable plasticization, cellulose acerate cannot be used as plastics.Blends of cellulose esters and aliphatic polyesters have been prepared during these several years by western investigators using melt compounding. Compatibility of the cellulose esters and the polyesters is the main subject to be investigated, but the … More object of this studies is to realize practical and biodegradable plastics from the cellulose esters. Under these background, we have been also trying to develop biodegradable plastics from cellulose esters and ethers by using a reactive processing procedure. This procedure includes oligoesterification of cellulose derivatives or likes with some hydroxyl groups remained. This causes a grafting, that is, an internal plasticization. It was found that the bleeding-out of the homo-oligomer, which is acting as external plasticizer, can be depressed, when the amounts of grafting become larger. Dicarboxylic acid anhydrides and monoepoxides or glycerine, epsilon-caprolactum and monoepoxides are successfully reacted in the presence of cellulose acetates at a relatively high temperature under certain torque by which all the compounds are melted, resulting in biodegradable plastics. In this concern, a new technique could be developed, by which grafted oligomers chemically bonded to CA can be separated from homo-oligomers quantitatively and completely. In its extension, methodology and conditions are pursued to improve the amounts of grafting. Less