利用废纸制作的新型热塑性材料生物降解性能及机理研究

Traditional petroleum-derived plastic constitutes a serious environment pollution problem, because it is hardly degradable in the natural environment. Fully biodegradable material was given a lot of study, but its utilization and development was limited by its high price. The preparation of the new biodegradable material was a new way for resource recovery of solid waste –wastepaper, and solving environment pollution problem.. In prophase research, the cyanoethyl modification of wastepaper was conducted. The preparation and properties of the new biodegradable material were investigated. Screening and identification of a cyanoethylated wastepaper-degrading strain were study as well. The results showed that the biodegradable material was effectively degraded by celluloses. The environmental microbiology study method was used to screen and identify microbial strains which could degrade the biodegradable material firstly; Then, the biodegradation property, the law and the mechanisms of the biodegradable material were studied，which was degraded by microbial strains; At last, in order to investigate the environmental value of the biodegradable material, biodegradation property of the material was studied, which was disposed by land fill and composting. The research provides a new way for utilization of wastepaper.

传统塑料来自于石油资源，且在自然环境中很难降解，废弃后严重污染环境。现大量研究的全生物降解材料由于价格昂贵而限制了其广泛应用和发展，利用废纸改性制作生物降解材料是固体废物资源化和解决上述问题的有效途径之一。. 在前期工作中完成了利用废纸氰乙基化改性制作新型热塑化材料工艺研究以及降解菌的筛选与鉴定的初步探索研究，表明此新材料具有生物降解性。本项目拟在此基础上，首先采用环境微生物学的研究方法筛选获得降解新型热塑性材料的微生物菌种和菌群，然后研究新型热塑性材料在所筛选菌种和菌群作用下的生物降解性能、规律和机理，最后通过研究材料在固体废物堆肥和填埋处理过程中的降解性能，并以此分析材料的环保价值，获得具有良好的力学性能和生物降解性能的材料，为固体废物废纸的高附加值利用奠定基础。

传统塑料来自于石油资源，且在自然环境中很难降解，废弃后严重污染环境。现大量研究的全生物降解材料由于价格昂贵而限制了其广泛应用和发展，利用废纸改性制作生物降解材料是固体废物资源化和解决上述问题的有效途径之一。在前期研究的基础上，采用环境微生物学的研究方法筛选和鉴定出六株菌：A2属于Ochrobactrum sp.；A4属于Brevibacillus sp.；A5属于Pseudomonas sp.； B1属于Pseudomonas sp.；C2属于Brevibacillus sp.；C5属于Brevibacillusparabrevis strain。对这六株菌进行复配，获得降解效果最好的菌株组合是C2、A4、C5，接种最优比例为C2∶A4∶C5=1∶2∶1，且发现C5菌株在体系中与A4、C2菌株有拮抗作用。通过单因素和正交实验获得混合菌降解氰乙基化废纸材料的最佳降解条件为：蛋白胨浓度1 g/L，吐温-80加入量 0.3 %，pH值=8，温度33℃，摇床转速140 rpm，培养时间为3 d，氰乙基化废纸的降解率为20.68%，培养温度对降解菌的生长和降解效率影响较大。微生物降解氰乙基化废纸的过程中存在着将纤维素链上的取代基团的碳氮三键转化为碳氢键的过程，且经微生物降解后的材料结晶结构被破坏，分子间作用力减弱。由于材料的固体废物堆肥和土壤填埋处理实验的失败，未获得具有良好的力学性能和生物降解性能的材料，这为固体废物废纸的高附加值利用提供了基础数据和研究经验。