Crystallization of bisphenol‐A polycarbonate. I. Influence of trimellitic acid tridecyloctyl ester on the kinetics of crystallization

Abstract

The crystallization of bisphenol‐A polycarbonate plasticized by trimellitic acid tridecyloctyl ester (Morflex 525) has been studied. A half‐crystallization time of 100 min is observed at 170°C with 10% of plasticizer compared with a figure of 18,000 min for the unplasticized material. The kinetic study is limited to the primary crystallization process which can be described by an Avrami equation; however, the Avrami coefficients are much higher than usual. Studies on the effect of the preparation procedure of the samples and of premelting indicate that nucleation is at least partially heterogeneous.

Optical properties of plasticized polycarbonate

“…It is well known that plasticizers improve the molecular mobility of the polymer, which may facilitate crystallization of the polymers having a regular structure whose molecular mobility without a plasticizer is small 4–7. Polycarbonates are a typical example of such polymers.…”

“…Heating and the presence of solvents or plasticizers facilitate crystallization. In the latter case, owing to depression of the viscosity of the polymer system and increasing the polymer chain mobility, ‘induced’ crystallisation is observed 4–7. However, it may be expected that, if the plasticizer has a branched molecular structure and some groups of its molecules interact strongly enough with the polymer, crystallization will not take place and polycarbonate and PC wares will remain amorphous and possess good optical properties.…”

Isothermal Crystallization of Poly(tetrafluoroethylene). Effect of Holding Time in the Melt on Calorimetric Measurements

“…6 -12 The presumption that PTFE can retain some kind of order in the melt is in line with the outcome of a number of studies on the effect of melt holding time on the isothermal crystallization behaviour of polymers such as polyethylene, 13 poly(ethylene oxide), 13 poly(ethylene terephthalate), 14 -16 poly-( ethere ether ketone), 1 7 · 18 poly(phenylene sulfide), 19 • 20 and polycarbonate. 21 Many of the phenomena observed in these studies have been connected to self-nucleation by, for instance, Wunderlich in reference 22 which also provides quotations of similar studies on polymers not quoted above. The mechanism of self-nucleation, thereby microscopic remnants of polymer crystallites remain unmelted and can serve as nucleation sites on cooling below the melting temperature can be presumed to play a role also in the melt-crystallization of PTFE.…”

On crystallization of bisphenol-A polycarbonate thin films upon annealing

“…Bisphenol-A polycarbonate (BAPC) has been extensively investigated because of its outstanding properties, such as excellent selectivity, high impact resistance and high glass transition temperature [1][2][3][4][5][6][7][8][9][10]. The BAPC has a semi-rigid structure, which makes it exhibit low thermal crystallization rate and low crystallinity.…”