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http://dx.doi.org/10.9713/kcer.2011.49.2.206

Thermal and Mechanical Properties of Poly(lactic acid) Specimens Fabricated by Various Equal-channel Angular Extrusion Processes  

Liu, Xu-Yan (School of Applied Chemistry and Biological Engineering, Chungnam National University)
Jung, Si-In (School of Applied Chemistry and Biological Engineering, Chungnam National University)
Choi, Ho-Suk (School of Applied Chemistry and Biological Engineering, Chungnam National University)
Oh, Jun-Taek (ENET Co.)
Kim, Jong-Kuk (ENET Co.)
Publication Information
Korean Chemical Engineering Research / v.49, no.2, 2011 , pp. 206-210 More about this Journal
Abstract
We fabricated rod-like poly(lactic acid)(PLA) specimens through applying various methods of equal-channel angular extrusion(ECAE) process and investigated the change of thermal and mechanical properties of specimens before and after each ECAE process. Combining three re-injection routes(A, BC, and C) and three pass counts(1, 2 and 4) allowed us to fabricate 7 different PLA specimens. Thermal properties of each specimen were measured by both differential scanning calorimeter and thermo-gravimetric analyzer. Shear strains of each specimen with respect to applied loads were measured by indentation hardness tester. Field emmision scanning electron microscopy was used to observe internal microstructure of cross-section of each specimen. The observed microstructures qualitatively supported the explanation of hardness test results. Among 7 specimens, PLA-P2A showed the biggest shear strain probably due to its dense microstructure.
Keywords
Equal-Channel Angular Extrusion; Poly(lactic acid); DSC; TGA; Hardness Test;
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