可降解材料生物降解率的检测方法比较

Comparative evaluations of testing methods for the biodegradation rates of degradable materials

基于现行的材料降解率测定标准及特定微生物的降解性能,设计了4种材料降解率的检测方法,即++两种标准方法(接种物:腐熟堆肥、蛭石腐熟堆肥浸提液)和两种实验方法(接种物:蛭石芽孢杆菌、+蛭石嗜热菌).采用生产环保胶带所用的原纸、塑料薄膜(主要成分为polylactic acid,PLA)和胶带成品作为受测材料,对比不同处理方法下材料降解性能的效率.结果表明,在60 d的实验周期中,原纸和+PLA薄膜在4种方法处理下均呈现快速降解.然而,胶带成品降解率在腐熟堆肥、蛭石腐熟堆肥浸提液++处理下上升缓慢;在蛭石芽孢杆菌处理下略高;在蛭石嗜热菌处理下上升速率显著高于其他处理方法(约1.7~7.5倍).添加微生物菌剂尤其是嗜热菌,能有效提升产品降解率的测定效率.因此,优化降解接种物的方法可提高材料降解率的测试效率,有利于企业缩短可降解材料的研发及生产周期.

Herein,based on existing standards for the measurements of material degradation rates and the degradation abilities of microorganisms,four methods were designed to determine material degradation rates.These four methods included two standard methods(inoculums:composting,vermiculite+composting leachate)and two experimental methods(inoculums:vermiculite+Bacillus,vermiculite+thermophilic bacteria).For this,the raw paper and plastic film(polylactic acid,PLA)components of environmentally friendly tape,as well as the finished tapes,were used as test materials to compare the material degradation rates using the above methods.Throughout the 60-day test cycle,both the PLA films and raw paper presented high degradation rates according to the four methods.The degradation rate of finished tape products increased gradually under the composting and vermiculite+composting leachate treatment and marginally rapidly under the vermiculite+Bacillus treatment.Additionally,under the vermiculite+thermophilic bacteria treatment method,the finished tape materials displayed a markedly higher degradation rate than that produced by other methods(roughly 1.7~7.5 times).Thus,the addition of microorganisms,particularly thermophilic bacteria,enhances the testing efficiency of material biodegradation rates.Therefore,we suggest that the optimization of degradation cultures can improve the testing efficiency of material degradation parameters,allowing manufacturing enterprises to shorten the research and development cycles of biodegradable products.