Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576, Singapore.
Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576, Singapore.
Sci Total Environ. 2022 Mar 20;813:151880. doi: 10.1016/j.scitotenv.2021.151880. Epub 2021 Nov 23.
The modern economy that is fast-moving and convenience centric has led to excessive consumption of plastic. This has unwittingly led to egregious accumulation of plastic waste polluting the environment. Unfortunately, present means of plastic waste management have all been proven as less than adequate; namely recycling, landfill and incineration. Recent focus on plastic waste management has seen the confluence of the developments in biodegradable polymers and microbial engineering strategy for more expedient decomposition of plastic waste at composting facilities. This review paper is an assimilation of current developments in the areas of biodegradable polymer as well as microbial strategy towards management of polymer waste. Advents in biodegradable polymers have been promising, especially with aliphatic polyesters and starch in blends or co-polymers of these. Microbial strategies have been pursued for the identification of microbial strains and understanding of their enzymatic degradation process on polymers. New insights in these two areas have been focused in improving the rate of degradation of plastic waste at composting facilities. Recent alignment of testing and certification standards is outlined to give intimate insights into the mechanisms and factors influencing biodegradation. Despite recent milestones, economic viability of composting plastic waste in mainstream waste facilities is still a distance away. As it remains that a polymer that is biodegradable is functionally inferior to conventional polymers. Rather, it requires a shift in consumer behaviour to accept less durable biodegradable plastic products, this will then lower the threshold for biodegradable polymers to become a commercial reality.
快速发展和以便利为中心的现代经济导致了塑料的过度消费。这无意中导致了大量塑料垃圾的积累,污染了环境。不幸的是,现有的塑料废物管理手段都被证明是不够的;即回收、垃圾填埋和焚烧。最近对塑料废物管理的关注集中在可生物降解聚合物的发展以及微生物工程策略上,以更迅速地在堆肥设施中分解塑料废物。本文综述了可生物降解聚合物以及微生物策略在聚合物废物管理方面的最新进展。可生物降解聚合物的发展前景广阔,尤其是脂肪族聚酯和淀粉在这些聚合物的混合物或共聚物中。微生物策略已经被用于识别微生物菌株,并了解它们对聚合物的酶降解过程。这两个领域的新见解集中在提高堆肥设施中塑料废物的降解速度上。最近概述了测试和认证标准的调整,以深入了解影响生物降解的机制和因素。尽管最近取得了里程碑式的进展,但在主流废物设施中堆肥塑料废物的经济可行性仍然遥不可及。因为可生物降解的聚合物在功能上不如传统聚合物,仍然需要改变消费者的行为,接受耐用性较低的可生物降解塑料产品,这将降低可生物降解聚合物成为商业现实的门槛。