1 research outputs found
Effects of Poly(vinyl butyral) as a Macromolecular Nucleating Agent on the Nonisothermal Crystallization and Mechanical Properties of Biodegradable Poly(butylene succinate)
To improve the crystallization and
mechanical properties of polyÂ(butylene succinate) (PBS), a series
of polyÂ(vinyl butyral) (PVBs) with various degrees of polymerization,
have been synthesized as macromolecular nucleating agents. Nonisothermal
crystallization kinetics of PBS nucleated by the PVBs has been examined
via polarized optical microscopy and differential scanning calorimetry,
followed by detailed analysis with theoretical models. The PVBs are
found to significantly increase the number of spherulites and crystallization
temperatures by 11 °C, and to reduce the spherulite size from
80 to 3 μm and the activation energy from 133 to 53 kJ/mol.
Only Avrami and Tobin’s models are capable of well characterizing
the crystallization kinetics. The effects of the PVBs depend on their
concentration and the degree of polymerization, coupled with their
miscibility/immiscibility with PBS. Meanwhile, the nucleated PBS exhibits
a significant enhancement in mechanical properties: 69% in Young’s
modulus, 26% in tensile strength, and 14% in impact strength