Synthesis and properties of poly(butylene terephthalate)‐poly(ethylene oxide)‐poly(dimethylsiloxane) block copolymers

Abstract

Abstractchemical structure image Poly(butylene terephthalate)‐poly(ethylene oxide)‐poly(dimethyl siloxane)‐poly(ethylene oxide) block copolymers, (PBT‐PEO‐PDMS‐PEO)m, are synthesized by polycondensation (PC) of dimethylterephtalate (DMT), 1,4‐butanediol (BDO) and PEO‐PDMS‐PEO. The soft block has been incorporated from 10 to 70 wt‐%; the total molecular weight (MW) of the block‐copolymers amounts to 16000 ‐ 20000 g/mol.One major problem of polyether‐PBT thermoplastic elastomers is their poor thermo‐oxidative stability. Due to the excellent heat stability of PDMS, the resistance of this new thermoplastic elastomer against thermo‐oxidative degradation has been increased 80 %!From differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA) in the PEO‐PDMS‐PEO based COPEs, three phases can be distinguished. Besides the crystalline PBT phase, an amorphous mixed phase of PBT and PEO and an almost pure PDMS phase have been found. Due to the high concentration of the mixed PBT‐PEO phase, the low temperature modulus and the glass transition temperature, Tg, are not dominated by the pure PDMS phase (Tg = −114°C). Depending on the amount of PBT and PEO present, the main glass transition lies in the range of −50°C to 50°C.

Topography Mediated Regulation of Her-2 Expression in Breast Cancer Cells

“…PDMS has been used extensively to study cellÀsubstrate interactions, in medical implants and biomedical devices because of its biocompatibility, 21À24 low toxicity 22,25,26 and high oxidative and thermal stability. 27,28 In addition, the ability to fabricate micro-structures using soft-lithography have made this material attractive for use in cell biology studies, including contact guidance, chemotaxis and mechanotaxis. 29À32 Despite the several advantages of PDMS, its applications in medical implants and biomedical devices has been limited because PDMS is highly hydrophobic.…”

Cell Adhesion on Polyelectrolyte Multilayer Coated Polydimethylsiloxane Surfaces with Varying Topographies

“…PDMS has been used extensively to study cell-substrate interactions in medical implants and biomedical devices because of its biocompatibility, [16][17][18][19] low toxicity, 17,20,21 and high oxidative and thermal stability. 22,23 PDMS is elastic and optically transparent and has low permeability to water and low electrical conductivity. 24,25 These properties, in addition to the ease with which it can be fabricated into microstructures using soft-lithography, 26 have made this material attractive for use in cell biology studies, including contact guidance, chemotaxis, and mechanotaxis.…”

Direct Synthesis of Poly(dimethylsiloxane) Copolymers with TPE‐Properties via CuAAC (Click Chemistry)

“…This solution was then diluted with water and extracted three times with dichloromethane. The combined organic phases were dried over MgSO 4 , filtered and all volatiles removed under reduced pressure. Drying in vacuum yielded the polymer as an off-white to yellowish tacky gum or elastic solid in yields of 93%.…”