Mechanical and dielectric breakdown properties of PBT/TPE, PBT/PBT/PET, and PBT/antioxidant blends

Abstract

To improve the thermal aging flexibility of poly(butylene terephthalate) (PBT), PBT was melt-blended with three type thermoplastic elastomer [poly ether-ester type (TPE1), polyester-ester type (TPE2), and poly(buthylene 2,6-naphthalate)/poly(tetramethylene glycol) block copolymer type (TPE3)], PBT/poly(ethylene terephthalate), (PET) alloy (Alloy), and phosphate type antioxidant (T1). The content of the three type TPEs and Alloy was fixed at 20 parts per 100 g of PBT. The morphology and thermal behavior of these blends have been investigated with scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetry (TG). In the case of PBT/Alloy-20 and PBT/TPE3-20 blends show clean fractured surface, whereas for PBT/TPE1-20 and PBT/TPE2-20 blends, the elongated pieces or fiber can be seen abundantly which indicates a good compatibility. TG traces show a significant shift of the weight loss toward higher temperature for PBT/Alloy-20, whereas PBT/TPE1-20, PBT/TPE2-20 and PBT/TPE3-20 blend decrease in thermal stability than PBT. To investigate the applicability for insulation material, the prepared blend samples were extruded an electric wire and flexibility and electric breakdown voltage (BDV) of wire after thermal aging were studied. For PBT/TPE1-20 and PBT/TPE2-20 blends did not show any cracks after flexibility test at 130 C for 6 h and 225 C for 30 min. In contrast PBT, PBT/Alloy-20, PBT/TPE3-20, and PBT/T1-1 showed a partial crack in the insulation after flexibility test at 130 C for 6 h although its good flexibility at 225 C for 30 min.

Preparation and Characterization of Flame-Retarded Poly(butylene terephthalate)/Poly(ethylene terephthalate) Blends: Effect of Content and Type of Flame Retardant

“…Thus, development of PBT/PET blends has attracted a significant amount of attention from researchers and industry [13,14,15,16]. Blending PBT with PET achieves a product with high electrical insulation properties and good mechanical properties due to the synergistic effect of these two polyesters in the crystallization process [17]. Besides, the crystallization behavior of PET was significantly enhanced by blending with PBT, resulting in a lower glass transition temperature and melting temperature [18].…”

Influences of exfoliated graphite on structures, thermal stability, mechanical modulus, and electrical resistivity of poly(butylene terephthalate)

“…PBT has relatively rapid crystallization rate and high elasticity compared with poly(ethylene terephthalate) (PET), but it has somewhat lower strength and stiffness than PET. Nonetheless, because of its combining excellent mechanical properties with robust chemical resistance and dimensional stability, PBT has been widely used for an engineering thermoplastic1–3 or for a component in blends,4–9 copolymers,10–13 and composites 14–17. However, for high‐performance applications, thermal and mechanical properties of PBT need to be enhanced.…”

Enhanced PET processing with organophosphorus additive: Flame retardant products with added-value for recycling

“…p-aminobenzoic, 3,5-dihydroxybenzoic, and 4hydroxybenzoic acids are some examples of these stabilizers [43]. Organophosphoruscompounds such as triphenyl phosphate [44][45][46], triphenyl phosphite [46], phosphoric acid [44,47], bis(2,4dicumylphenyl) pentaerythritol diphosphate [48,49], and bis(2,4,di-tert-butylphenyl) pentaerythritol diphosphate [50], are also used to control thermal degradation of PET.…”