Study On The Toughening Of Polylactic Acid

This paper respectively melt mixing PBAT, PBS, PPC, ACR with PLA, melt mixing CaCO3and PLA,then testing, discovering the toughening effect of different materials on the PLA.PBAT, PBS and PPC, in some extent can improve the impact strength and elongation at break, of PLA. Therein PBAT had the most obvious effect which was showed the best compatibility, PBS take the second place, and followed by PCC; Along with the increasing of the content of PBAT, the impact strength of PLA/PBAT blend material has been gradually rose, the notched impact strength value was18.1kJ/m2, but two phase compatibility gradually became poorer. Use PBAT for PLA toughening which could prepared better toughness PLA material.Toughen PLA with ACR, pure polylactic acid (PLA) material and toughening agents ACR have been tested. PLA resin will not turn up heat degradation when processed under220℃, some degree of thermal degradation can be detected when processed temperature was over240℃. The results of impact strength, elongation at break properties test for PLA which compose of different content of ACR demonstrated that impact strength and elongation at break properties were growing as ACR was increased, maximum impact strength was up to28.03kJ/m2, elongation at break was reached91.2%.Toughen PLA via using CaCO3, CaCO3’s surface has strong polarity, and high specific surface area, it is easy to absorb water, hydroxyl can be absorbed by CaCO3’s surface. With coupling agent CaCO3processing method, by which the surface of CaCO3contact and react with one side of coupling agent, then formed chemically bond, meantime coupling agent reacted with another side of PLA which can increase the interactions between them and improve properties. Through the research of the reason of the growing of impact strength and elongation at break via PLA/CaCO3melting blend, improve CaCO3particles, which can enhance surface area, promote the chance of contact between PLA and the particles, increase the contact area and matrix. More of the silver crack and plastic deformation area can be produced when external stress was forced, the external energy is a largely absorbed which achieved toughen effect.