Related Experiment Video
Updated: Jan 23, 2026

The Effect of Construction and Demolition Waste Plastic Fractions on Wood-Polymer Composite Properties
Published on: June 7, 2020
Effect of molecular stereoregularity on the transcrystallinization properties of poly(l-lactide)/basalt fiber
Hongwei Pan1, Zengwen Cao2, Yunjing Chen2
1Key Laboratory of Polymer Ecomaterials, Chinese Academy of Sciences, Changchun Institute of Applied Chemistry, Changchun 130022, China; University of Chinese Academy of Sciences, No.19A Yuquanlu, Beijing 100049, PR China.
Abstract:
A comparative study on interfacial crystallization of poly(l-lactic acid) (PLLA) with different stereoregularity (PLLA2003D 96.0%, PLLA4032D 98.5%, and PLLA290 99.2%) surrounding macroscopic basalt fibers (BF) has been carried out in polymer composites. The effect of stereoregularity on the interface crystallization was systemically studied by microstructure. From polarized optical microscopy (POM) analysis, it was found that the transcrystallinity of PLLA was influenced by temperature. Moreover, stereoregularity significantly affects the crystallization kinetics. It was also found that increased molecular mobility providing faster orientation with high stereoregularity and low molecular weight. It might be the reason for the observation that the PLLA290 samples crystallized more rapidly than the PLLA4032D samples. Appropriate molecular stereoregularity exhibits a clear increase in extensional stress that is directly correlated with the crystalline orientation of the crystallization samples. The mechanism of formation of transcrystallinity underwent the process of "a mismatch in thermal expansion coefficients" with the extensional stress.
More Related Videos
Related Concept Videos
Kinetic Molecular Theory and Gas Laws Explain Properties of Gas Molecules
Physical and Chemical Properties of Matter
Molecular Models
Classifying Matter by Composition
According to its composition, the matter can be classified into two broad categories — pure substances and mixtures.
A pure substance is a form of matter that has a constant composition throughout with uniform properties. For example, any sample of sucrose has the same composition and same physical properties, such as melting point, color, and sweetness, regardless of the source from which it is isolated.
A mixture is composed of two or...
Molecular and Ionic Solids
Molecular Solids
Molecular crystalline solids, such as ice, sucrose (table sugar), and iodine, are solids that are composed of neutral molecules as their constituent units. These molecules are held together by weak intermolecular forces such as London dispersion forces, dipole-dipole interactions, or hydrogen bonds, which...
General Properties of Solutions

