摘要
合成了聚(对苯二甲酸乙二醇酯-共-对苯二甲酸异甘露醇酯-共-间苯二甲酸乙二醇酯-共-间苯二甲酸异甘露醇酯)(PEIIT).通过差示扫描量热分析(DSC)、紫外-可见-近红外光谱(UV-Vis-NIR)、X射线衍射(XRD)、偏光显微镜(POM)球晶培养等分析方法研究了PEIIT的结晶性能、光学性能及热性能.阐述了增加四元共聚酯PEIIT中间苯二甲酸结构单元的含量可以有效降低其结晶度和结晶速率的具体机制.间苯二甲酸结构单元含量的增加使PEIIT链段运动过程中的空间位阻增大,结晶能力降低,其冷结晶温度逐渐升高,热结晶温度逐渐降低直至不再有热结晶现象产生.由于结晶程度的降低,PEIIT的雾度可以完全降为零,并且透光率可以达到90.7%.同时发现了造成PEIIT透光率降低的吸光因素,黄变程度增加使330~550 nm波长的蓝紫光被PEIIT吸收,导致其透光率受到影响.PEIIT的熔点受间苯二甲酸含量变化影响较大,但仍保持了良好的耐热分解性能.
Poly（ethylene terephthalate-co-isomannide terephthalate-co-ethylene isophthalate-co-isomannide isophthalate）（PEIIT） was synthesized. The crystallization, optical and thermal performances of PEIIT were investigated by using differential scanning calorimetry（DSC）, ultraviolet-visible-near-infrared spectroscopy（UV-Vis-NIR）, X-ray diffraction（XRD） and polarized light microscopy（POM）. The results demonstrate that the crystallinity and crystallization rate of PEIIT can be reduced effectively with the increase of the content of isophthalic acid units in copolyester PEIIT. The increase of the content of isophthalic acid units made the steric hindrance of PEIIT molecular chains increase, resulting in the decrease of crystallization ability, which is mainly because its cooling crystallization temperature gradually rise and the melt crystallization temperature gradually decrease until no generation of thermal crystallization phenomenon. Due to the decrease of the crystalline part, the haze of PEIIT can be completely reduced to zero, and the light transmittance can reach 90.7%. At the same time, it was found that the decrease of PEIIT light transmittance stems from the increase of yellowing degree, which makes the blue violet light of 330~550 nm wavelength absorbed by PEIIT, leading to the low light transmittance. The melting point of PEIIT is greatly affected by the content of isophthalic acid, but it still maintains good thermal decomposition performance.
出处
《有机化学》
SCIE
CAS
CSCD
北大核心
2017年第12期3229-3235,共7页
Chinese Journal of Organic Chemistry
关键词
异甘露醇
间苯二甲酸
缩聚
光学性能
结晶性能
isomethanol
isophthalic acid
polycondensation
optical performance
crystalline performance
