Tailoring Crystallinity of Electrospun Plla Fibres by Control of Electrospinning Parameters

Abstract

Poly(L-lactic acid) (PLLA) fibers were fabricated by electrospinning. The effects of various electrospinning process parameters on the thermal properties, especially the crystallinity of the electrospun fibers were investigated. Thermal analysis of the fibers revealed that they exhibited degree of crystallinity ranging from 23% to 46% while that for the as-received granules was approximately 37%, suggesting that the crystallinity of electrospun PLLA fibres can be controlled by optimizing the electrospinning process. This finding is very important because crystallinity affects polymer properties such as degradation, stiffness, yield stress, modulus and tensile strength, solubility, optical and electrical properties which will in turn affect the behavior of these materials when they are utilized in energy, environment, defense and security applications. The results presented in this paper show that the degree of crystallinity of the electrospun fibers decreased with increasing the polymer solution concentration. Furthermore, an optimum electrospinning voltage at which maximum degree of crystallinity can be obtained was observed. At voltages higher or lower than the optimum electrospinning voltage, the degree of crystallinity will decrease or increase, respectively. The effect of the needle tip to collector distance (NTCD) on the degree of crystallinity follows no predictable and consistent pattern.

Titanium Nanorods Loaded PCL Meshes with Enhanced Blood Vessel Formation and Cell Migration for Wound Dressing Applications

“…Observed decreases in degree of crystallinity at higher concentration of TNR might be due to the poor dispersion and subsequent agglomeration of TNR in PCL, which disturb the crystallization process. Decrease in overall crystallinity of polymers affects the tensile strength, and the results of tensile results agree with this . Earlier studies also showed that crystallinity of PCL decreases with the addition of higher quantity (above 2% w/w) of nanoparticles such as ZnO in polymer matrix which can be due to the agglomeration of nanoparticles at higher concentration …”

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The Influence of Pre‐Electrospinning Plasma Treatment on Physicochemical Characteristics of PLA Nanofibers

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