聚（β－羟基丁酸酯）／聚双酚A羟基醚共混体系相容性及结构的研究

ＤＳＣ和ＦＴＩＲ测试表明，结晶／非晶共混体系聚（β－羟基丁酸酯）（ＰＨＢ）／聚双酚Ａ羧基醚是部分相容的。熔融结晶退火可以大大提高共混物的结晶度，增加其相容性。７５／２５组分ＰＨＢ相结晶度最大，５０／５０组分晶面微晶尺寸最大。     

聚β-羟基丁酸酯/聚氧化乙烯共混体系力学性能研究

本文详细研究了可完全生物降解的聚 β 羟基丁酸酯 (PHB)与水溶性聚氧化乙烯 (PEO)两元共混体系的拉伸力学性能 .讨论了PEO分子量、共混组成及热处理条件对共混体系力学性能的影响 .其中 ,PHB与超高分子量PEO(重均分子量 5× 10 6)共混 ,两组分力学上具有相容性 ,共混物的拉伸强度、断裂伸长率及模量都有明显的正的协同效应 .共混改性效果显著PHB的力学性能得到很大改善 ,尤其PHB的脆性缺陷 .并且 ,共混物在经过适当温度退火处理之后 ,共混物性能还可进一步改善     

拉伸状态下弹性聚醚酯聚集态结构和分子运动的固体高分辨核磁共振研究

用固体高分辨核磁共振碳谱方法对不同拉伸比的聚醚酯嵌段共聚物的聚集态结构和分子运动进行了研究,发现共聚物中的聚四氢呋喃(PTMO)链段在拉伸比为2 0时开始就出现结晶,且结晶度和晶片厚度都随着拉伸比增加而明显增加,而样品中未结晶部分的高频分子运动随拉伸比的变化则不明显,拉伸导致的PTMO结晶主要发生在“纯”的PTMO非晶区.通过1 H自旋扩散实验,估算出在拉伸比为4 . 0倍时,PTMO非晶区与结晶区的界面层厚度为1 .1nm ,PTMO非晶区与硬段的结晶区的界面厚度约为3 .1nm .     

聚(β-羟基丁酸酯)和β-羟基丁酸酯-β-羟基戊酸酯共聚物与可生物降解高分子共混改性研究进展

总结了近年来聚(β-羟基丁酸酯)、β-羟基丁酸酶—β-羟基戊酸酯共聚物与可生物降解高分子共混物的相容性、结晶性、热性能、加工性能、力学性能和生物降解性能。通过共混。聚(β-羟基丁酸酯)与—β-羟基丁酸酶卢羟基戊酸酯共聚物的性能得到显著改善。     

聚(β-羟基丁酸酯)和β-羟基丁酸酯-β-羟基戊酸酯共聚物共混改性研究进展

综述了近年来聚(β-羟基丁酸酯)和β-羟基丁酸酯-β-羟基戊酸酯共聚物经共混改性所得到的共混物的相容性、结晶性、热性能、加工性能、力学性能和生物降解性能。     

P(HB-co-HV)/PVPh的相容性与聚集态结构

采用差热扫描分析、红外光谱、固体核磁、小角X光散射等方法研究了聚(β-羟基丁酸酯-co-β-羟基戊酸酯(P(HB-co-HV))/聚(对-羟基苯乙烯)(简称PVPh)共混物的相容性和形态。结果表明两组分间形成较强的分子间氢键,形成完全相容的共混体系。固体核磁结果表明P(HB-co-HV)/PVPh(50/50)在3.4nm尺寸上是完全均相的。小角X光散射结果表明,在等温结晶的共混物中无定形的PVPh分子分散在P(HB-co-HV)片晶之间与非晶的P(HB-co-HV)分子形成非晶区,从而使非晶区加宽,长周期增加。     

PHBV-GMA与PHBV-GMA/PPC共混物中接枝物的热性能与形态结构

以甲基丙烯酸缩水甘油酯(GMA)单体对聚(3-羟基丁酸酯-3-羟基戊酸酯)(PHBV)接枝改性,得到的产物PHBV-GMA与封端后的聚碳酸亚丙酯(PPC)反应性共混。索氏抽提器提取PHBV-GMA和PHBV-GMA/PPC共混物,分别得到两种接枝产物PHBV-g-GMA和PHBV-g-PPC,用差示扫描量热法(DSC)、偏光显微镜(POM)以及原子力显微镜(AFM)研究其热性能和形态结构。结果发现,GMA接枝后,对PHBV结晶有成核效应。PPC接枝PHBV后,接枝物PHBV-g-PPC结晶度降低,球晶尺寸减小,PHBV和PPC两种大分子间的相分离程度降低,相容性明显提高。     

梳型聚醚-聚磺酸锂共混物的锂离子导电性

本工作合成了聚甲基丙烯酸齐聚氧化乙烯酯和聚甲基丙烯酸己磺酸锂两系列聚合物,研究共聚物结构对共混物的相容性和锂离子导电性的影响.结果表明,共混物的相容性是决定离子电导率的主要因素;共混物内锂离子传导发生在非晶区,聚合物的链段运动是离子传导的主要推动力.     

梳型聚醚-聚磺酸锂共混物的锂离子导电性

 本工作合成了聚甲基丙烯酸齐聚氧化乙烯酯和聚甲基丙烯酸己磺酸锂两系列聚合物,研究共聚物结构对共混物的相容性和锂离子导电性的影响.结果表明,共混物的相容性是决定离子电导率的主要因素;共混物内锂离子传导发生在非晶区,聚合物的链段运动是离子传导的主要推动力.     

聚（β－羟基丁酸酯）／聚双酚A羟基醚共混体系相容性及结构的研究

ＤＳＣ和ＦＴＩＲ测试表明，结晶／非晶共混体系聚（β－羟基丁酸酯）（ＰＨＢ）／聚双酚Ａ羟基醚（ＰＢＨＥ）是部分相容的．熔融结晶退火可以大大提高共混物的结晶度，增加其相容性，７５／２５组分ＰＨＢ相结晶度最大，５０／５０组分（０２０）、（１３０）晶面微晶尺寸最大．ＳＡＸＳ研究表明，纯ＰＨＢ的中间层约为１．５ｎｍ，片层厚约４．０ｎｍ；共混物的中间层在２．０ｎｍ左右，片层厚在５．０—７．２ｎｍ之间，５０／５０组分片层最厚．７５／２５组分晶相和非晶相的密度差最大．     

聚β—羟基丁酯酯／超高分子量聚氧化乙烯共混体系相容性和结晶行为

为了解决废弃塑料引起的“白色污染”问题,世界各国竞相研制开发可生物降解高分子材料,其中,有关聚β羟基丁酸酯［ｐｏｌｙ（βｈｙｄｒｏｘｙｂｕｔｙｒａｔｅ）（ＰＨＢ）］的研究尤其活跃．然而,由于商品价格较高,材料本身抗冲击性能较差、加工窗口较窄等限制...     

聚β-羟基丁酸酯/超高分子量聚氧化乙烯共混体系相容性和结晶行为

为了解决废弃塑料引起的“白色污染”问题,世界各国竞相研制开发可生物降解高分子材料,其中,有关聚β 羟基丁酸酯［ｐｏｌｙ（β ｈｙｄｒｏｘｙｂｕｔｙｒａｔｅ）（ＰＨＢ）］的研究尤其活跃．然而,由于商品价格较高,材料本身抗冲击性能较差、加工窗口较窄等限制...     

聚环氧乙烷/聚乙基■唑啉共混体系结晶行为及相容性的研究

用偏光显微镜（ＰＬＭ）、ＤＳＣ、ＩＲ和ＷＡＸＤ等测试方法对聚环氧乙烷（ＰＥＯ）／聚乙基唑啉（ＰＥＯｘ）共混体系结晶行为及相容性进行了研究．结果表明，ＰＥＯ含量在３０％以上的共混体系中，几乎完全被球晶充满，非晶态ＰＥＯｘ作为微区分散在大球晶之间或之中；含量为２０％的共混体系照片上呈树枝状晶；含量低于１０％时则看不到结晶出现，体系形成单一的非晶相．对任何组成的共混物，均只出现单一的玻璃化转变温度（Ｔｇ），而且符合Ｆｏｘ方程揭示的规律；随ＰＥＯｘ组分含量的增加，共混体系的结晶度减小，熔点下降，并利用平衡熔点方程计算出ＰＥＯ与ＰＥＯｘ的相互作用能密度．非晶ＰＥＯ与ＰＥＯｘ热力学相容，其相容性是由于这两种分子间存在着特殊相互作用．ＰＥＯｘ的加入不会改变ＰＥＯ的晶胞参数．     

Effect of aging on fractional crystallization of poly(ethylene oxide) component in poly(ethylene oxide)/poly(3‐hydroxybutyrate) blends

The effect of aging on the fractional crystallization of the poly(ethylene oxide) (PEO) component in the PEO/poly(3‐hydroxybutyrate) (PHB) blend has been investigated. The partial miscibility of the PEO/PHB blends with high PEO molecular weight (M_v = 2.0 × 10⁵ g/mol) was confirmed by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis. The fractional crystallization behavior of the PEO component in the PEO/PHB blends with low PEO content (not more than 30 wt% of PEO), before and after aging under vacuum at 25 °C for 6 months, were compared by DSC, fourier transform infrared microscopic spectroscopy, small angle X‐ray diffraction, and scanning electron microscopy. It was confirmed that nearly all the PEO components remain trapped within interlamellar regions of PHB for the PEO/PHB blends before aging. Under this condition, the crystallization of PEO is basically induced by much less active heterogeneities or homogeneous nucleation at high supercoolings. While, after the same PEO/PHB samples were stored at 25 °C in vacuum for 6 months, a part of the PEO component was expelled from the interlamellar region of PHB. Under this condition, the expelled PEO forms many separate domains with bigger size and crystallizes at low supercoolings by active heterogeneous nucleation, whereas the crystallization of PEO in the interlamellar region is still mainly induced by less active heterogeneities or homogeneous nucleation at extreme supercoolings. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2665–2676, 2005     

Dielectric relaxation study of atactic poly(epichlorohydrin)/poly(3-hydroxybutyrate) blends

Binary blends of atactic poly(epichlorohydrin) (aPECH) and poly(3-hydroxybutyrate) (PHB) were investigated as a function of blend composition and crystallization conditions by dielectric relaxation spectroscopy. The quenched samples were found to be miscible in the whole composition range by detecting only one glass transition relaxation, for each composition, which could be closely described by the Gorden-Taylor equation. The cold-crystallized blends displayed two glass transition relaxations at all blend ratios indicating the coexisting of two amorphous populations: a pure aPECH phase dispersed mainly in the interfibrillar zones and a mixed amorphous phase held between crystal lamellae. The interlamellar trapping of aPECH was small and decreases with increasing the overall PHB content in the blend. At high crystallization temperatures the aPECH molecules was found to reside mainly in the interfibrillar regions due to its high mobility relative to the crystal growth rate of PHB. Our results suggest that because the intersegmental interaction in aPECH/PHB blends is weak, the mobility of the amorphous component at a given crystallization temperature decides diluent segregation.     

固体高分辨核磁共振研究聚氧乙烯/纳米二氧化硅复合物的界面相互作用

采用固体高分辨核磁共振碳谱对聚氧乙烯(PEO)/纳米二氧化硅(Nano-SiO₂)复合物体系的相态结构、分子间相互作用和分子运动进行了研究,发现随着复合物中SiO₂含量增加,PEO结晶度明显降低,且PEO非晶区的分子运动受到明显约束,基于对PEO非晶区及SiO₂颗粒表面羟基质子的自旋-自旋弛豫行为的分析,提出了复合物的界面模型以及SiO₂与PEO之间的界面相互作用机制.     

Computer simulation studies of the miscibility of poly(3-hydroxybutyrate)-based blends

By means of the molecular dynamics simulation method, the miscibility of poly(3-hydroxybutyrate)/polyethylene (PHB/PE) blend has been investigated. Two glass transition temperatures of the PHB/PE are found by scrutinizing its volume-temperature curve, and this result is qualitatively in agreement with the experimental results. To further analyze the miscibility of poly(3-hydroxybutyrate)-based blends, the Flory-Huggins parameters of PHB/PE, poly(3-hydroxybutyrate)/poly(ethylene oxide) (PHB/PEO), poly(ethylene oxide)/polyethylene (PEO/PE) have been calculated via a Monte Carlo scheme, and the morphology of the PHB/PEO and the PHB/PE blend has been simulated using dissipative particle dynamics method. The time evolution of dividing interface for PHB/PEO/PE blend shows a dynamic phase separation process. All these results indicate that PHB and PEO tend to mix together, whereas PE aggregates to form PE-rich domains in the PHB/PE and PHB/PEO/PE blends.     

环氧树脂/聚氧化乙烯共混物及其与硫氰化钠络合物的结构研究(Ⅰ)

对不同分子量聚氧乙烯(PEO)以不同比例与双酚A二缩水甘油醚型环氧树脂(ER)制得的交联共混物ER/PEO,以及再与NaSCN络合后的产物用WAXD,SAXS,DSC和SEM等方法进行了研究,结果表明:随着ER含量的增加,ER/PEO共混物由晶态转为非晶态。ER/PEO属单斜晶系;与NaSCN络合后,体系结晶性变差。ER/PEO-NaSCN属三斜晶系,其长周期比相应ER/PEO交联共混物的长周期值大。EP的加入使非晶层增厚,结晶片层变薄,长周期值增加。