Hydrolysis of poly(l-lactic acid) using microwave irradiation

Hirao, Koichi; Shimamoto, Yoshie; Nakatsuchi, Yuta; Ohara, Hirotaka

doi:10.1016/j.polymdegradstab.2009.10.003

Cited by 21 publications

(10 citation statements)

References 8 publications

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“…Another advantage is the preferential absorption of energy by target compounds with high dielectric loss and high polarity in the reaction mixtures and acceleration of specific and selective reactions . Over the past three decades, this technology has been widely used in analytical chemistry, synthetic organic and polymer chemistry, composite processing, environmental engineering, and wood liquefaction applications.…”

Section: Introductionmentioning

confidence: 99%

Alkaline extraction of xylan from wood using microwave and conventional heating

Panthapulakkal

Kirk

Sain

2014

J of Applied Polymer Sci

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This study aims to investigate the effect of microwave heating versus conventional heating for the alkaline hydrolysis of xylan from birch wood to understand the effect of the heating process on the dissolution of wood, the yield of xylan, and the degree of polymerization of the isolated xylan. The results indicate that the rate of wood dissolution is significantly higher (0.020/s) during microwave extraction than the conventional extraction (0.001/s). Wood solubilization, after an initial rapid removal of damaged fibers, is linear with time for both conventional and microwave extraction, with microwave showing a rate 20 times faster. The yield of xylan reaches a limit of about 60% for both processes but then declines slowly as thermal degradation become significant. Microwave heating provides 60% yield in 1/10th the time of the conventional process. This is found to be associated with the rapid temperature rise, and also with local "hot spots" generated during microwave treatment. The results indicated that xylan degradation was significant above 95 C. The nature of the isolated xylan was different for the two heating methods: the xylan isolated using microwave extraction for 20 min exhibits higher molecular weight (i.e., a greater degree of polymerization, about 150) than the xylan isolated using conventional extraction for the same duration (degree of polymerization, about 124) demonstrating the effectiveness of microwave heating for extraction of xylan from wood.

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Section: Introductionmentioning

confidence: 99%

Alkaline extraction of xylan from wood using microwave and conventional heating

Panthapulakkal

Kirk

Sain

2014

J of Applied Polymer Sci

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“…Microwave irradiation is known to heat materials more efficiently compared to conventional method. Based on previous research, chemical reactions process will faster by microwave irradiation (Hirao et al, 2009). It is not only improved the reaction time but also the power of microwave will effect on protein content.…”

Section: Chitin Isolation (Deproteination and Demineralization) Undermentioning

confidence: 99%

Influence of Microwave Irradiation on Extraction of Chitosan from Shrimp Shell Waste

Apriyanti

Susanto

Rokhati

2018

Reaktor

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Chitosan is natural polysaccharides which is nontoxic, biodegradable, and biocompatible and have many advantages in various kinds of fields including health, food, agriculture, and industry. Chitosan usually take long time to extract by conventional method for deacetylation process of chitin. Raw material for chitosan can be found in shrimp shell waste. Chitosan manufactures usually need high temperatures and chemicals in large quantities and it takes much time and consumes a lot of energy where will give bad effect to the environment. Recently microwave irradiation as nonconventional energy sources is widely used in chemical reactions. To reduce the impact of environmental pollution due to excessive use of chemical treatment, the objective of this work is processing chitosan under microwave irradiation. Expected production of chitosan with the same mass requires fewer chemicals than conventional heating. In particular, the study will examine the effect of making the chitosan and adding chemicals, reaction time and operating temperature and degree of deacetylation in chitosan with conventional heating methods that the results will be compared using a microwave. In this research will be developed to the design and fabrication of prototype scale extractor for manufacturing chitosan from shrimp shell waste after optimum results obtained from the research laboratory scale. From the research we can conclude that microwave will speed up reaction time. FTIR also showed functional group of chitosan formed from microwave irradiation have same results. Keywords: chitosan, shrimp shells, microwave

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“…This revealed rapid degradation of atactic segments with a decreased rate of hydrolysis for increasing stereoblock length. The temperature of hydrolysis could be reduced to 170 • C by the application of microwave heating, as demonstrated by Ohara et al [76]. With conventional heating, 800 min are required to achieve the maximum lactic acid yield, which is achieved within 120 min with microwave irradiation.…”

Section: Pla Hydrolysis-to Lactic Acidmentioning

confidence: 99%

The Chemical Recycling of PLA: A Review

McKeown

Jones

2020

Sustainable Chemistry

144

118

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Plastics are an indispensable material with numerous benefits and advantages compared to traditional materials, such as glass and paper. However, their widespread use has caused significant environmental pollution and most plastics are currently nonrenewable. Biobased polymers represent an important step for tackling these issues, however, the end-of-life disposal of such materials needs to be critically considered to allow for a transition to a circular economy for plastics. Poly(lactic acid) (PLA) is an important example of a biobased polymer, which is also biodegradable. However, industrial composting of PLA affords water and carbon dioxide only and in the natural environment, PLA has a slow biodegradation rate. Therefore, recycling processes are important for PLA, particularly chemical recycling, which affords monomers and useful platform chemicals, maintaining the usefulness and value of the material. This review covers the different methods of PLA chemical recycling, highlighting recent trends and advances in the area.

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Hydrolysis of poly(l-lactic acid) using microwave irradiation

Cited by 21 publications

References 8 publications

Alkaline extraction of xylan from wood using microwave and conventional heating

Alkaline extraction of xylan from wood using microwave and conventional heating

Influence of Microwave Irradiation on Extraction of Chitosan from Shrimp Shell Waste

The Chemical Recycling of PLA: A Review

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