【作者】 乔宇；

【导师】 付中玉；

【作者基本信息】 北京服装学院 ， 材料学， 2010， 硕士

【摘要】 聚对苯二甲酸丙二醇酯(PTT)是一种性能优异的新型聚酯,其特殊的结构和优良的物理化学性能,使之在纺织、工程塑料、薄膜等领域获得广泛应用。由于PTT大分子链上存在的三个亚甲基而导致的区别于PET和PBT的“奇碳效应”,使得PTT聚酯纤维能够同时克服PET的刚性和PBT的柔性,并兼有PET和PA的优点,如优异的回弹性、易加工性、易染色性以及蓬松性等。聚乙二醇(PEG)本身就是一类相变焓较高、热滞后效应低的储能材料,作为组分时常被用来研制新型相变材料。本文通过直接酯化-缩聚反应路线合成了不同分子量的聚对苯二甲酸丙二醇酯(PTT)和聚对苯二甲酸丙二醇酯/聚乙二醇共聚物(PTT-PEG)。利用红外光谱法(FTIR),差示扫描量热法(DSC),热失重(TG),核磁共振(1HNMR)等现代化分析技术分析研究了PTT和PTT-PEG的结构特征相变行为、储热性能及热性能的影响因素,分析了此类聚醚酯嵌段共聚物以PEG为软段、PTT为硬段的固-固相变材料的能量贮存和相变机理。研究了用直接酯化法合成聚对苯二甲酸丙二醇酯(PTT)的工艺,考察了影响合成工艺的各种因素,采用直接缩聚法,选择PTA/PDO摩尔比为1:1.6;催化剂用量为3.68/万;缩聚反应温度在265℃是非常合适的;通过共聚反应合成了PEG相对分子质量不同和含量不同的PTT-PEG嵌段共聚物,以DSC法表征了共聚物在常温下的相变性能。结果表明:当用于共聚的PEG相对分子质量达到4000以上时,制得的共聚物才具有良好的常温相变性能;且相变焓随PEG含量的升高而升高,但PEG的含量与初始PTA的质量比达到40%后相变焓反而下降。用FTIR,1HNMR表征了PTT-PEG共聚物的结构,结果表明其是以PTT硬链段封端的多嵌段共聚物。通过改变加入的PEG相对分子质量和PEG/PTA投料比可控制PET-PEG嵌段共聚物相转变的热性能。PTT-PEG共聚物作为常温相变材料时,PEG的总量与PTA的比控制在40%,其中PEG6000与PEG4000的含量为60%和40%时为最佳。结果表明:该PTT-PEG相变材料具有良好的储热性能,相变温度适中,热性能稳定,相变过程中不产生液体,其相变实质是聚醚软段PEG由结晶固态转变为非晶固态的过程。更多还原

【Abstract】 Poly(trimethylene terephthalate) is a new kind of polyester, which will be widely used in textile、engineering plastics、films etc. for its special structure and outstanding physical and chemical properties. Because of the exist of three phenylenes which lying in macromolecular chain will generate“The Effect of odd carbon”, and lead to different performances from PET and PBT. Thus the PTT fiber can not only have the rigidity of PET and the flexible of PBT synchronously, but also doubles the virtues of PET and PA such as high resilience, easier process and dye etc. Polyethylene glycol(PEG) itself is a kind of phase change material with high enthalpy and low thermal hysteresis. It is often used to synthesis novel phase change materials as working groups. In this paper, poly trimethylene terephthalate(PTT) with various molecular weights,poly trimehtylene terephthalate-poly ethylene glycol(PTT-PEG) block copolymers were prepared by the direct esterification and polycondensation.FTIR, DSC, TG, 1HNMR were used to study the structural characteristics,phase-change behavior, heat storage characteristics and phase change mechanism of the novel solid-solid phase change heat storage copolymer which features PEG-based soft segment and PTT-based hard segments.The influent factors on synthesis process of PTT were discussed. The optimized process conditions of a direct esterification way were: charge ratio of 1:1.6, catalyst amount: 3.68×10-4mol/mol PTA, polycondensation temperature: 265℃. PTT-PEG block copolymers with varied PEG molecular and different contents were synthesized by copolymerization. The phase-change properties in the normal temperature were scanned by DSC. The result showed that the copolymers have gained increasing phase-change properties after the molecular weight of PEG which was used in the copolymerization exceeded one particular numerical value. The phase-change enthalpy of copolymers had an increasing aftermath with the increasing of PEG contents, but it was proved that the volume heat would decrease when the initial charge ratio of PEG/PTA exceeded 40%. By FTIR and 1HNMR, it was proved that the macromolecular chain was polyblock sealed by hard segment. The content of PEG segments depended on the ratio of PEG/PTA which was added to the system from the beginning. We can control the phase-change characteristic of PTT-PEG block copolymers by changing the molecular of PEG and the ratio of PEG/PTA. When its phase-change characteristic is asked to perform under normal temperatures, we can set the charge ratio of PEG/PTA as 40%, including 60%PEG6000 and 40%PEG4000.The results showed that the PTT-PEG copolymers have good thermal properties: appropriate transition temperature, good thermal stability, and no liquid leakage in the phase-change process. The heat storage mechanism is indeed the transition process of the soft segment of PEG from crystalline state to amorphous.更多还原