摘要
2020年6—12月,在崇明生态岛“两无化”水稻种植基地进行大田实验,检测并分析了生物降解地膜的微观形貌、化学结构、相对分子量,探究不同厚度生物降解地膜的降解以及物理化学性质的变化。结果表明:随着覆膜时间延长,不同厚度的生物降解地膜表面均出现孔洞且数量逐渐增多;生物降解地膜中聚己二酸/对苯二甲酸丁二酯(PBAT)可能发生了诺里什Ⅱ型反应,导致高分子材料分子链的断裂;生物降解地膜相对分子量均先增后减,地膜中高分子在稻田环境中发生了的断裂、重组、分解,形成分子量相对较小的降解物;覆膜135 d时厚度为0.0100、0.0090、0.0085 mm的生物降解地膜的数均分子量分别比初始下降了15.32%、28.54%、22.88%,重均分子量则分别下降了17.00%、21.73%、16.21%。
In order to study the degradation process and mechanism of biodegradable mulch with different thickness,the field experiment was carried out in paddy field without chemical fertilizer or pesticide in Chongming eco-island from June to December,2020,and the microscopic morphology,chemical structure and relative molecular weight of biodegradable mulch film were examined and analyzed.The results showed that holes appeared on the surface of biodegradable mulch films with different thicknesses and the number of holes gradually increased with the extension of mulching time.PBAT in biodegradable mulch films might have undergone NorrishⅡreaction,resulting in a break in the molecular chain of the polymeric material.The relative molecular weight of biodegradable mulch films increased first and then decreased,and the macromolecules in the films were broken,reorganized and decomposed in the field environment and degradable products with relatively small relative molecular weight were generated.Compared with the initial state,the number average molecular weight of biodegradable films with thicknesses of 0.0100,0.0090,0.0085 mm decreased by 15.32%,28.54%and 22.88%,while the weight average molecular weight decreased by 17.00%,21.73%and 16.21%,respectively.
作者
宋欣
沈峥
乔恒波
石惠娴
司慧萍
张亚雷
SONG Xin;SHEN Zheng;QIAO Hengbo;SHI Huixian;SI Huiping;ZHANG Yalei(National Engineering Research Center of Protected Agriculture,Tongji University,Shanghai 200092;State Key Laboratory of Pollution Control and Resource Reuse,Tongji University,Shanghai 200092)
出处
《环境污染与防治》
CAS
CSCD
北大核心
2022年第1期51-54,共4页
Environmental Pollution & Control
基金
上海市崇明区生态农业科创项目(No.2019CNKC-08)。
关键词
生物降解地膜
厚度
“两无化”水稻田
降解特性
biodegradable mulch film
thickness
paddy field without chemical fertilizer or pesticide
degradation characteristic
