Study of crystallization behavior of poly(phenylene sulfide)

Abstract

Poly(phenylene sulfide) (PPS) is an engineering thermoplastic polymer that presents high temperature resistance (glass transition temperature around 85 ºC and melting point at 285 ºC). These properties combined with its mechanical properties and its high chemical resistance allows its use in technological applications such as molding resins and as matrix for structural thermoplastic composites. During the manufacture of thermoplastic composites, the polymer is exposed to repeated melting, quenching and crystallization processes. The properties of semicrystalline polymers, such as PPS, depend on its crystallization behavior. This work deals with the PPS crystallization kinetics under different thermal cycles. This study was performed under isothermal conditions in a differential scanning calorimetry (DSC), coupled to Perkin Elmer crystallization software referred to as Pyris Kinetics -Crystallization. The results were correlated with microscopic analyses carried out in a polarized light microscope, equipped with a controlled heating and cooling accessory. In this case, the experimental conditions were the same adopted for the DSC analyses. From the results, parameters could be established to be used in the composite manufacture.

Efeito da degradação ambiental nas propriedades de cisalhamento de compósitos PPS/fibra de carbono

“…Dentre as matrizes termoplásticas utilizadas em compósitos de aplicações estruturais, o poli (sulfeto de fenileno) (PPS) é um termoplástico de engenharia especial, ou seja, um polímero cuja estrutura é composta por anéis aromáticos, que intercalados a átomos de enxofre, impõem restrições à movimentação da cadeia polimérica. Esta estruturação resulta em uma cadeia homopolimérica linear, com uma elevada cristalinidade entre 50 e 60% e que permite sua aplicação em elevadas temperaturas, devido o baixo coeficiente de dilatação térmica e alta resistência ao fogo, além de resistir a ataques químicos de solventes orgânicos, inorgânicos, sais e bases [3][4][5][6][7][8][9][10] . Durante condições operacionais, componentes em compósitos poliméricos são normalmente expostos a tensões mecânicas e ataques ambientais de agentes externos responsáveis pela perda de propriedades mecânicas.…”

Overall Investigation of Poly (Phenylene Sulfide) from Synthesis and Process to Applications—A Review

“…Furthermore, DSC and polarized light microscopy (PLM) techniques are popularly used to characterize the isothermal crystallization process, not only in the domains of metals but also in polymers and composites domains. Liliana et al . studied the isothermal crystallization behavior of PPS by DSC and PLM techniques.…”

Effects of UV Light on Mechanical Properties of Carbon Fiber Reinforced PPS Thermoplastic Composites

“…In the heating process, both fiber and matrix are heated beyond the melting temperature (T m ) of the thermoplastic matrix. In the study by Nohara et al, an optimal processing tmperature can be achieved by analyzing the thermal cycle and crystallization kinetics of the matix (PPS). At a temperature of 295 °C the study shows that the polymer is still under melting process and high volume of crystals are visible, hence the application of pressure at this temperature may damage the fibers.…”