Environmental Degradation of PLA

Understanding the environmental degradation of PLA is very important because more than 100,000 MT of PLA are produced annually — mainly for consumer products and packaging. Therefore, most of this PLA wdl be disposed in landfill sites after a short period of use. PLA undergoes biodegradation via 

This leads to the question, how long does it take for PLA products to fully degrade Kale et al. (2007) conducted a biodegradability study on polylactide bottles in real and simulated composting conditions. The study used PLA 500 ml bottles used for packaging spring water sold by Biota of America. The PLA bottles were fabricated by NatureWorks. The PLA was 

Further investigation of PLA biodegradation using the cumulative measurement respirometric (CMR) system (according to ASTM D5338 and ISO 14855-1) showed that the biodegradation of PLA bottles required 30 days buried in a compost pile to achieve 80% mineralization. CMR is a system designed to yield 

The reaction scheme for titration is described in ASTM D5338 as follows. A strong mineral acid HCl is used. 

During absorption of CO2 generation from biodegradation of samples  

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Abiotic hydrolysis is the most important reaction for initiating the environmental degradation of synthetic polymers (Gbpferich 1997) such as PE (Gu 2(X)3), PTT (Heidary and Gordon 1994), PLA, and their copolymers (Hiltunen et al. 1997 Nakayama et al. 1996). The degradation of most synthetic plastics in nature is slower than that of natural polyesters. This process involves environmental factors, followed by the action of microorganisms in their surroundings (Albertsson et al. 1994 Cruz-Pinto et al. 1994). 

Positive outcomes from the addition of a plasticizer into PLA are the increase in the environmental degradability at the end-of-life treatments. In fact, the slow degradation rate of neat PLA is often considered to be a major drawback for biomedical applications, leading to long in vivo life-time, which could be up to years in some cases. Solutions to increase the abiotic degradation rate in biomedical applications could be an inspiration to optimize the degradation of PLA in other applications, such as food packaging. 

In addition to the importance of an effective and controlled hydrolytic degradation of PLA for its environmental and hiomedical applications, in... 

Eco-friendly biodegradable polymers and biocomposites are relatively novel materials that can contribute to reduce the dependence on fossil sources. Because of their renewable nature and biodegradability, environmentally benign composite materials with properties comparable to those of some widely used commodities can be produced. Py-GC/MS has developed as a useful tool for the study of thermal degradation of such polymers and composites, and many studies have recently been published for biodegradable polymers, such as polycaprolactone (PCL), polyhydroxyalcanoates (PHAs) and their copolymers,poly(lactic acid) (PLA), and carbohydrates, including starch and cellulose. 

A continuous increase in oil prices and environmental concerns about the use of common petroleum-based plastics have recently led to a growing interest in bio-based plastics. Poly(lactic acid) (PLA), a plastic derived from fermented plant starch, is fast becoming one of the popular alternatives to traditional petroleum-based plastics. Even though PLA has been known for more than a century, it has only been used commercially in recent years in a number of biocompatible/ bioabsorbable biomedical device market, packaging applications, and so on. A number of factors contribute to the success of PLA in these applications, including its physical properties as well as favorable compostable and degradation characteristics [1]. 

PLA has been ciurently received a lot of attention for commodity applications because of environmental degradability and sustainable biomass resources. The crystal structure, crystallization behavior and even nucleating agents can greatly determine the mechanical and thermal properties of PLA. 

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