Issue 14/2015 - Progress in polylactic acid/biomass composites

Compared with petroleum-based plastics, polylactic acid has excellent biodegradability, and it can replace petroleum-based plastics on a large scale in the field of disposable injection molding, foaming and blown film to solve the increasingly serious problem of "white pollution", and has been vigorously promoted
around the world.
However, polylactic acid has problems such as poor heat resistance, high price and poor toughness, and the bio-based polymer materials research team of Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences has conducted in-depth research on this and made a series of progress
.

In the previous work, the team successfully solved the key problem of poor heat resistance of polylactic acid by synthesizing bio-based crystallization nucleating agent for polylactic acid, thereby expanding the application range of polylactic acid in traditional plastics and other related fields, but this heat-resistant modification will further increase the cost of polylactic acid and further limit its application in
disposable applications.

In response to this problem, the research team used highly reactive bio-based compatibilizers such as epoxy soybean oil, epoxy cashew phenol shell oil, itaconic acid epoxy resin, citric acid epoxy resin, etc.
for the first time to conduct interface modification studies on these composites, and prepared a fully bio-based degradable and environmentally friendly polylactic acid composite material
with high performance and meeting the application requirements.

The highly active reactive bio-based compatibilizer improves the interfacial compatibility of polylactic acid/biomass filler, realizes the infiltration of hydrophobic polylactic acid at the interface of hydrophilic biomass filler, and improves the interfacial compatibility and mechanical properties
of such composites.
Finally, through this method, the researchers prepared a variety of injection molding and blister disposable degradable products that meet the application needs, which is expected to effectively alleviate the environmental problem of
"white pollution" in the near future.

(Ning)