A new approach in compatibilization of the poly(lactic acid)/thermoplastic starch (PLA/TPS) blends

Abstract

a b s t r a c tIn this study, a new compatibilizer was synthesized to improve the compatibility of the poly(lactic acid)/thermoplastic starch blends. The compatibilizer was based on maleic anhydride grafted polyethylene glycol grafted starch (mPEG-g-St), and was characterized using Fourier transform infrared spectroscopy (FTIR), dynamic mechanical thermal analysis (DMTA) and back titration techniques. The results indicated successful accomplishment of the designed reactions and formation of a starch cored structure with many connections to m-PEG chains. To assess the performance of synthesized compatibilizer, several PLA/TPS blends were prepared using an internal mixer. Consequently, their morphology, dynamic-mechanical behavior, crystallization and mechanical properties were studied. The compatibilizer enhanced interfacial adhesion, possibly due to interaction between free end carboxylic acid groups of compatibilizer and active groups of TPS and PLA phases. In addition, biodegradability of the samples was evaluated by various methods consisting of weight loss, FTIR-ATR analysis and morphology. The results revealed no considerable effect of compatibilizer on biodegradability of samples.

Effect of PVA and PDE on selected structural characteristics of extrusion-cooked starch foams

“…For example, the addition of PLA increased the mechanical properties and resistance to water of final products [15] . TPS/PLA blends are characterized by improvement in thermal stability, inhibition of starch retrogradation and higher resistance to water at high relative humidity [29][30][31] .…”

From microstructure to mechanical properties of compatibilized polylactide/thermoplastic starch blends

“…[1][2][3] However, there are a number of limitations from application standpoint that may make challenging the use of PLA. [7][8][9] The introduction of starch into the PLA matrix produces a low cost and eco-friendly polymer blend. One of the mostly treated strategies applied in this sense is the blending of PLA with other polymers, especially biodegradable ones.…”

The effect of MDI on the structure and mechanical properties of poly(lactic acid) and poly(butylene adipate-co-butylene terephthalate) blends

“…This had been widely investigated and believed to be attributed to the melting and recrystallization mechanism. 43,49,50 As the chain extension interfered in the crystallization process, many imperfect crystallites could be formed, and a large number of terminal groups and branched points generated imperfect crystallization. 51 In comparison with those of the neat PLA, the melting peak shape and amount of the blends exhibit almost no change.…”