Syndiotactic polystyrene: crystallization and melting behaviour

Isothermal and nonisothermal melt‐crystallization kinetics of syndiotactic polystyrene

“…This is evidence that the process of sPS isothermal melt crystallization is very fast. The result is consistent with the result of Cimmino et al 5 The crystallization half-time, t 1/2 , is defined as the time at which the extent of crystallization is 50% completed and is determined from the measured kinetic parameters:…”

Effect of Compressed CO2 on Phase Transitions and Polymorphism in Syndiotactic Polystyrene

“…For neat sPS, the value 2.7 for n obtained in this work is similar to the values between 2 and 3 reported in the literature. 5 On treatment with CO 2 , n tends to decrease, suggesting a possible change in nucleation type or crystal growth geometry. 40 It should be noted that under the T and p conditions used for investigating isothermal crystallization, the crystalline form of sPS is the same, i.e., the planar mesophase (see below).…”

“…At 41 atm, the kinetics were so fast that the complete crystallization peak could not be recorded, as the polymer had already achieved maximum crystallinity before the temperature of the DSC could be stabilized. The crystallization kinetics were analyzed using the Avrami equation, 5,40 where X t is the extent of crystallinity induced at time t, log…”

“…1,2 It has good temperature and chemical resistances and is a potential engineering thermoplastic due to favorable crystallization kinetics and a wide processing window. 3,4 The crystallization rate of sPS from the melt is about 2 orders of magnitude higher than that of isotactic polystyrene under similar supercooling conditions 5 and it can attain crystallinity levels up to 70% with a melting point close to 270°C. 6,7 There are four types of crystalline form, R, , γ, and δ, and two types of mesomorphic form.…”

Polymorphic crystal forms and morphology of syndiotactic polystyrene in miscible states

“…Thus, its crystallization behavior is critical for understanding its mechanical properties. Earlier, the crystallization and melting behavior of neat s-PS have been studied by Cimmino et al, 17 where they reported that the dimension of spherulites ranged between 30 and 80 m for isothermal temperatures of 240 -255°C. This size is in agreement with what we observed in this study.…”