Isothermal Crystallization and Melting Behavior of Composites Composed of Poly(L-lactic Acid) and Poly(glycolic Acid) Fibers

Abstract

Several composites of poly (L-lactic acid) (PLLA) with poly (glycolic acid) (PGA) fibers were prepared. The isothermal crystallization kinetics and melting behavior of PLLA and all of the composites were characterized by using differential scanning calorimetry. The experimental data were processed by using the Avrami equation. The relative parameters, such as the Avrami exponent and half-time crystallization, revealed that PGA fibers had positive effects on the crystallization of PLLA, but these effects had only a minimal dependence on the PGA fiber content. Moreover, at low isothermal crystallization temperatures (85 • C∼110 • C), recrystallization during the heating scan was observed, which could lower the melting point of the samples to a certain extent.

Estimating the Relative Crystallinity of Biodegradable Polylactic Acid and Polyglycolide Polymer Composites by Machine Learning Methodologies

“…Chen et al utilized the solvent method to fabricate several PLLA/PGA composites with 2–8 weight percent (wt%) of the PGA fiber [ 12 ]. The differential scanning calorimetry (DSC) technique was employed to study the effect of PGA fibers on the isothermal crystallization of fabricated composites [ 12 ].…”

“…Chen et al utilized the solvent method to fabricate several PLLA/PGA composites with 2–8 weight percent (wt%) of the PGA fiber [ 12 ]. The differential scanning calorimetry (DSC) technique was employed to study the effect of PGA fibers on the isothermal crystallization of fabricated composites [ 12 ]. Table 1 shows the range of conducted experiments to measure relative crystallinity as a function of time, temperature, and PGA dosage in the considered polymers.…”

“…Although PLLA has relatively satisfactory mechanical characteristics, its crystallization rate is slow. Hence, the fabrication of composites [ 9 ] based on PLLA with a better crystallization behavior has been suggested [ 10 , 11 , 12 ]. Chen et al synthesized several completely biodegradable PLLA-based composites by dispersing polyglycolide (PGA) fibers in the PLLA body [ 12 ].…”

“…Hence, the fabrication of composites [ 9 ] based on PLLA with a better crystallization behavior has been suggested [ 10 , 11 , 12 ]. Chen et al synthesized several completely biodegradable PLLA-based composites by dispersing polyglycolide (PGA) fibers in the PLLA body [ 12 ]. Several laboratory-scale investigations have been carried out to examine the effect of crystallization time, temperature, and PGA fiber dosage on the relative crystallinity of pure PLLA and PLLA/PGA composites [ 12 ].…”

“…Generally, the application domain of polymers is directly related to their physicochemical properties, including their tensile strength, elasticity, glass transition temperature, solubility, and crystallinity [ 12 ]. Crystallization is among the most complicated and longest-standing challenges related to polymer [ 13 , 14 , 15 ], composite [ 16 ], and zeolite [ 17 ] research and development.…”