Preparation And Application Study Of Cyclic Butylene Terephthalate Oligomers Resin

Cyclic butylene terephthalate oligomers (CBT) is a kind of important resinmaterials with special molecular structure which generates many excellent properties,such as low viscosity of the melt, no volatile organic compounds(VOC) in meltingprocess, good compatibility with other resin materials. CBT is a kind of thermoplasticresin, but it can be processed by the way of producing thermosetting resin. CBT resinhas been applied in many fields which need high demand to materials includingbuilding materials, sport equipments, transportation means, food packaging, and soforth.However, the domestic application of CBT resin is limited. Although we havethe patents for CBT resin production, it needs several years for large scale productionof CBT. So now all requirements need to be imported abroad but this directly lead tothe high price of CBT resin and impose restrictions on the application of CBT resin ina great degree. Therefore, finding a new method with high productivity and low costto produce CBT resin will be a great task to get rid of the dependence on importedproducts and expend the domestic application of it as well.This thesis proposes a method for preparation of the CBT resin called PhaseTransfer Interfacial Condensation which using the property of CBT to preparePBT/MMT composites via CBT resin ring-opening polymerization with catalystexistance. Due to the CBT with the very low viscosity, it was added to resin materialsto improve the reology of the resin melt, and the main conclusions of this study arelisted as below:(1) The preparation and characterization of CBT resin were showed as follow.We adopt Phase Transfer Interfacial Condensation and use terephthaloyl chlorides and1,4-butanediol as raw materials, methylene dichloride as organic phase, aqueoussolution as aqueous phase, CTAB as the emulsifier as well as HCl which is the by-product getting from the neutralization of NaOH. The product was CBT molecular structure charactered by infrared spectroscopy(IR) and hydrogen nuclear magneticresonance(1HNMR).(2) Montmorillonite was modified with PEG-P via solution intercalation method.Test methods including contact angle testing, IR, small angle X-ray diffraction(SXRD) test, etc. The results showed that modified montmorillonite was changedfrom hydrophilic to hydrophilic, and PEG-P entered into montmorillonite interlayersuccessfully.(3) The preparation and characterization of PBT/montmorillonite compositeswere showed as follow. Montmorillonite was modified with PEG-P to improvethe degree of dispersion in CBT melt. It can prepare the MMT by making use of theproprieties of the PEG-P. The SEM results showed that PBT/modifiedmontmorillonite composites was prepared successfully.(4) The improving effect of CBT resin on the liquidity of the PP melt wasshowed as follow. The change of the liquidity of the PP melt was reflected byanalysing the change on the balance torque of the mixture in molten state. The resultsindicated that the liquidity of PP melt can be enhanced effectively just by adding1%amount of CBT resin.