Wednesday, June 14, 2017

PLA from PolySciTech used as precursor for synthesis of environmentally-safe adhesives

Adhesives are used for manufacturing just about everything in our everyday lives. Most of these are petroleum-based materials, which creates an environmental concern due to their chemical off-gassing and lack of degradability. There is an increasing push in polymer science to replace non-degradable synthetics, or petroleum-based materials, with more sustainable alternatives. This becomes increasingly necessary as there is only a limited amount of landfill space available. Poly(lactic acid) (PLA) is a biodegradable polymer which naturally hydrolyzes into non-toxic lactic acid upon contact with water. Lactic acid itself is actually edible (it’s the ingredient that gives Korean kimchi its distinctive tangy-flavor) and can be easily metabolized by a wide variety of organisms back into carbon dioxide and water. For this reason, PLA is a very environmentally safe alternative in comparison to other polymers. However, typical PLA is not considered an adhesive. Recently, researchers at Purdue University utilized several PLAs from PolySciTech (www.polyscitech.com) (PolyVivo Cat# AP035, AP114, and AP138) as precursors to synthesize environmentally-safe poly(lactide)-catechol based adhesives. This research holds promise for the creation of environmentally safe alternatives to petroleum-type adhesives. Read more: Jenkins, Courtney L., Heather M. Siebert, and Jonathan J. Wilker. "Integrating Mussel Chemistry into a Bio-Based Polymer to Create Degradable Adhesives." Macromolecules (2017). http://pubs.acs.org/doi/abs/10.1021/acs.macromol.6b02213

“Adhesives releasing carcinogenic formaldehyde are almost everywhere in our homes and offices. Most of these glues are permanent, preventing disassembly and recycling of the components. New materials are thus needed to bond and debond without releasing reactive pollutants. In order to develop the next generation of advanced adhesives we have turned to biology for inspiration. The bonding chemistry of mussel proteins was combined with preformed poly(lactic acid), a bio-based polymer, by utilizing side reactions of Sn(oct)2, to create catechol-containing copolymers. Structure–function studies revealed that bulk adhesion was comparable to that of several petroleum-based commercial glues. Bonds could then be degraded in a controlled fashion, separating substrates gradually using mild hydrolysis conditions. These results show that biomimetic design principles can bring about the next generation of adhesive materials. Such new copolymers may help replace permanent materials with renewable and degradable adhesives that do not create chronic exposure to toxins.”


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