PROPERTIES AND CRYSTALLIZATION OF PLLA BIOPOLYMERS WITH CELLULOSE NANOCRYSTALS AND ORGANIC PLASTICIZER

Abstract

The paper deals with the research of ternary nanocomposites based on PLLA nucleated by lignin coated cellulose nanocrystals (L-CNC) and simultaneously modified with an acetyl tributyl citrate (ATBC) plasticizer. The potential synergistic effect of both additives on the crystallization and morphology of nanocomposites is evaluated by differential scanning calorimetry (DSC) and scanning electronic microscopy (SEM). Mechanical properties were evaluated by tensile tests and fracture toughness measurements. DSC analysis showed a synergistic effect of both additives on the crystallization of PLLA. Ternary composites which were plasticized by 10 mass% of ATBC and simultaneously nucleated by L-CNC (1 and 5 mass%) increased the degree of crystallinity up to 2.5 times and manage to eliminate undesired cold crystallization during reheating. A dramatic increase in ductility, associated with a decrease in tensile strength and modulus, was observed with the incorporation of ATBC at 10 mass%. The ductility of the PLLA/10ATBC and PLLA/10ATBC/1L-CNC composites increased from 3 % (PLLA) up to 160 % and 300 %, respectively. Furthermore, SEM analysis showed that higher concentrations of spray-dried L-CNC (5 mass%) are difficult to disperse by used technology. These agglomerates subsequently act as stress concentrators that initiate premature failure of the composites. Although a suitable combination of tensile characteristics was achieved, PLLA/10ATBC/1L-CNC composites still show relatively low Charpy impact strength (15 kJ/m2).

Recommended articles

MULTIDIMENSIONAL DESIGN OF TECHNOLOGY FOR OBTAINING SOLID LUBRICANT COATING ON TOOL HARD ALLOY

Alexander Shmatov, Lubomir Soos, Zdenko Krajny
Keywords: Thermo-hydrochemical treatment | solid lubricant coating | tool | hard alloy

CONTROL OF RADIAL INCREMENT AND WINDING DENSITY OF COMPOSITE CYLINDRICAL SHELLS

Alex Kutin, Gennady Aryassov, Victor Musalimov, Trieu Minh Vu, Reza Moezzi, Jindrich Cyrus
Keywords: winding | thread tension | winding process control | adaptive control

APPLICATION OF NEW RULES FOR PATTERN SPECIFICATION ACCORDING ISO GPS

Karel Petr
Keywords: pattern specification | GPS | tolerance zone pattern | constraint | geometrical tolerancing | simultaneous requirement | drawing descriptions | .

ABOUT WEAR RESISTANCE OF LINEAR BLOCK-POLYURETHANES

Volodymyr Mykolajovych Anisimov, Anton Panda, Volodymyr Volodymyrovych Anisimov, Konstantin Dyadyura, Iveta Pandova
Keywords: linear block-polyurethane | wear resistance | coefficient of friction | Hardness | molecular weight | content of rigid blocks | counterbody roughness | thermal diffusion surface saturation