Preparation And Properties Of Medical Transparent Polyether Ester Elastomer

The performance ofthermoplastic polyether ester elastomer is decided by the polyester hard segments and soft polyether segments.By selecting the appropriate dicarboxylic acids,the polyether ester elastomer can be synthesized by glycols and polyether with a chemical resistance?heat resistance?creep resistance?anti-radiation?high strength etc.But often,the polyether ester elastomer has a strong crystallinity,limiting its application in the medical field as a transparent polymer material.By adjusting the monomer synthesis process to improve and optimize the synthesis process,it can solve the polyether ester elastomer optically clear question.Selecting 1,4-cyclohexanedicarboxylic acid(CHDA)and 1,4-cyclohexanedimethanol(CHDM)as the raw material,in the polycondensation reaction tank at a reduced pressure,a series of poly-1,4-cyclohexane 1,4-cyclohexanedicarboxylic acid dimethyl ester(PCCD)can be synthesised esterification and polycondensation under reduced pressure using a two-step synthesis.Through the feed ratio,condensation temperature,polymerization time and other conditions were studied to determine the best formula and process parameters.By Fourier transform infrared spectroscopy(FT-IR)and nuclear magnetic resonance(NMR),the molecular structure of PCCD polyester were characterized.By gel permeation chromatography(GPC),the molecular weight(Mn)and the distribution(PDI)of the PCCD polyester were studied that the molecular weight PCCD polyester varied in different formulations and processes vary greatly.In order to compare the transparency of the PCCD polyester by to analyze its transparency,the results of the UV spectrophotometer show that the transmittance rate of PCCD polyester was above 80%.In order to investigate the reasons of the PCCD polyester with good transparency,the differential scanning calorimetry(DSC)and X-ray diffraction(XRD)were used,the test results of PCCD polyester sample show that:PCCD polyester is the amorphous polymers,very difficult to form spherulites,the crystallite size is less than the wavelength of visible light when irradiated with visible light diffracted to their sample to make a higher light transmittance.PCCD polyester had a good thermal stability.Selecting CHDA,CHDM and polytetramethylene ether polyol(PTMEG,Mn = 1000)as the raw material,in the polycondensation reaction tank in a reduced pressure,a series of different proportions of hard and soft segment PCCD-PTMEG elastomers were synthesised with normal pressure and reduced pressure esterification condensation.Using Fourier transform infrared spectroscopy(FT-IR)and nuclear magnetic resonance(NMR),the molecular structure of PCCD-PTMEG elastomers were characterized.The optical properties of PCCD-PTMEG elastomers through a haze analysis meter found that hard segment PCCD polyester content increased from 20%to 70%,the transmittance rate is more than 85%,and grow:ing,and the haze was declined aftera stabilization.This is because the hard segment PCCD with microcrystalline has the region transparent performance,when there were fewer microcrystalline zone,the degree of microphase separation was increased,the haze was big too.PCCD-PTMEG elastomers were done the crisp cross-section sample,it was found when the hard segment ratio was less,the micro-phase separation was improved,the multi-phase structure inside the refractive index difference was larger,the haze along was larger too;when the proportion of hard segment was more,micro-phase separation was not observed.With the increase of hard segment content,PCCD-PTMEG elastomers micro crystals increases,the degree of crystallinity increases,physical crosslinking point increased,tensile strength and Young's modulus were greatly improved;while the gap impact strength,elongation at break and elongation of 100%permanent deformation display has excellent toughness.The 100%elongation PCCD-PTMEG elastomers showed the elastic material is preferably.