显微镜图像分析研究聚丙烯/尼龙1010共混物相结构及其性能

用扫描电子显微镜图像分析研究了聚丙烯/聚酰胺1010共混物及其部分相容体系的相形态结构,计算了表征相结构和尺寸的结构参数,如分散相的平均直径、平均弦长和分散相的质心相关距等.并分别讨论了聚丙烯/聚酰胺1010共混物及其部分相容体系的相形态以及其结构参数与共混物组成的关系.测定了聚合物及其共混物体系的力学性能,讨论了共混物组成与力学性能的关系.聚丙烯/聚酰胺1010共混物的拉伸模量与组成的关系较为复杂,但其部分相容体系的拉伸模量与组成呈线性关系.聚丙烯/聚酰胺1010及其共混物体系的屈服强度与共混物组成均呈线性关系.表征相结构的两相平均弦长比(l-1/-l2)与组成以及共混物体系力学性能与组成的关系,二者相似.同时讨论了体系力学性能随相尺寸等的变化规律.     

PP/PS共混体系相结构形成与演变

以连续共混过程中间歇出料法研究了聚丙烯(PP)/聚苯乙烯(PS)体系共混过程中的扫描电镜图样演化过程,利用小角激光散射(SALS)证明了PP/苯乙烯-乙烯-丙烯嵌段共聚物(SEP)/PS体系的部分相容性,同时说明SALS研究聚合物熔体动态过程的有效性.针对扫描电镜图样,用重心粒径dg这一结构参数研究了PP/PS体系共混过程,利用分布函数求取了分散相PP分形维数,对共混过程中相分散进行了研究.     

多相聚合物体系熔体动态过程中相形成与发展——PS/PcBR非相容体系的扫描电子显微镜图样分析

以连续共混过程间歇出料法研究了PS/PcBR非相容体系共混过程中的扫描电子显微镜图样演化过程 ,从平均粒径、特征长度Λ和平均特征长度Λm 多个方面讨论了非相容体系的共混过程 ,并以标度函数P(Λ/Λm)证明非相容体系共混过程在一定时间和空间范围内具有自相似性 ,且分形维数D可以作为一个参数描述熔体动态过程     

非相容聚合物体系熔融共混过程中分散相粒径变化的预测

以PS PP共混体系为研究对象 ,研究了非相容聚合物体系混炼过程中分散相含量、剪切速率及聚合物弹性等对分散相粒径变化的影响 ,对平衡态分散相粒径的变化进行了预测 ,并对其计算公式进行了新的改进 .研究表明 ,分散相浓度较低时 ,分散相粒径与分散相体积分数呈线性增长关系 ;在较高浓度时 ,分散相粒子的聚结作用明显 ,公式应加以修正 .实验中还观察到 ,对于PS(连续相 ) PP(分散相 )共混体系 ,随着剪切速率的增大 ,分散相粒径先不断减小 ,达到一极小值后 ,却又有所增大     

高分子共混物梯度相结构形成过程中的界面效应

通过在高分子共混物内部引入不同的第三相界面,系统地研究了退火热处理条件下该界面对于共混物梯度相形态形成的影响.对具有一定初始粒径的共混物体系或初始近似为均相的共混体系,在第三相界面的诱导下,均能形成梯度相形态.探讨了诱导界面间距与体系相结构的关系.结果表明,当两个诱导界面间距小于所生成梯度层厚度的两倍时,梯度结构趋于交叠.继续减小诱导界面间距,则梯度结构趋于消失,诱导界面间共混物中分散相粒子快速长大,界面的诱导作用遍布整个样片,证实了我们所提出的“高分子共混物中二维条件下界面诱导加速分散相粒子粗化凝聚”的结论.     

等离子体条件下PP／PS共混体系组成和相结构的关系

运用等离子体装置制备了聚苯乙烯预聚物(PSt)并对聚丙烯(PP)进行了表面处理,得到改性聚丙烯(gPP)。在密炼机中以间歇出料法制备了不同组成的聚丙烯(PP)/聚苯乙烯(PSt)和改性聚丙烯(gPP)/聚苯乙烯(PSt)共混物。针对扫描电镜图样,用投影面直径dp这一结构参数研究了组成对两个共混体系相尺寸的影响以及相应的相分散状况。利用分布函数求取了分散相聚苯乙烯(PSt)分形维数,对不同组成的相分散进行了研究。     

高分子共混物梯度的相结构形成过程中的界面效应

通过在高分子共混物内部引入不同的第三相界面,系统地研究了退火热处理条件下界面对于共混物梯度相形态形成的影响,对具有一定初始粒径的共混物体系或初始近似为均相的共混体系,在第三相界面的诱导下,均能形成梯度相形态。探讨了诱导界面间距与体系相结构的关系。结果表明,当两个诱导界面间距小于所生成梯度层厚度的两倍时,梯度结构趋于交叠。继续减小透导界面间距,则梯度结构趋于消失,诱导界面间共混物中分散相粒子快速长大,界面的诱导作用遍布整个样片,证实了我们所提出的“高分子共混物中二维条件下界面诱导加速分散相粒子粗化凝聚”的结论。     

聚合物共混物脆韧转变性能研究Ⅱ.准韧性聚合物共混物脆韧转变的几何模型

给出了分散相粒间基体层厚度T与分散相粒径(d)、粒径分散度(σ)和分散相体积分数()的定量关系式.发现σ对T的影响与有关,不仅T随σ的增大而增大,而且越大,这种影响越显著.用计算机图像分析仪直接测定了聚氯乙烯/丁腈橡胶、聚丙烯(PP)/三元乙丙橡胶、PP/乙烯-醋酸乙烯酯共聚物共混物的T,发现这三种共混物的T近似于对数正态分布.理论预示与实验结果很好符合.     

二次电子衬度曲线法研究PVC/MBS共混物断面的分形特征

利用二次电子衬度曲线法测定了聚氯乙烯甲基丙烯酸甲酯丁二烯苯乙烯共聚物(PVCMBS)共混物冲击断面的形貌特征及对应的分形维数值.结果表明,材料的断口或微观结构并不是严格的分形结构,这种自相似性仅存在于一定尺码范围内,不同断面形貌特征所对应的分形维数测量值不同,随着MBS用量增加,PVCMBS共混物缺口冲击强度随满足自相似原理的形貌特征所对应的分形维数值增大而增大.本文从理论上讨论了材料断裂韧性与分形维数的关系.     

聚烯烃共混物分散相尺寸梯度分布形态形成速度影响因素的研究

研究了聚烯烃高分子共混物的初始相形态及相间界面张力的改变对退火热处理条件下共混物分散相尺寸分布梯度形态形成速度的影响．通过控制共混物共混过程中Ｂｒａｂｅｎｄｅｒ转子的转速来控制共混物所受的剪切力大小，可达到控制共混物初始相形态的目的．通过ＳＥＭ电镜观察相形态，并利用计算机图象分析仪得到分散粒子的粒径及其分布数据．研究结果表明，转子转速越大，即共混物所受的剪切力越大，分散相初始粒径越小，且分散也越均匀．初始粒径较小的样品退火后形成梯度的速度相对较快．选用体系聚丙烯（ＰＰ）／乙烯 醋酸乙烯酯共聚物（ＥＶＡｃ）、聚乙烯（ＰＥ）／ＥＶＡｃ及改变ＥＶＡｃ中的醋酸乙烯酯（ＶＡｃ）含量与ＰＥ共混对比研究了不同相界面张力对梯度化速度的影响．结果表明，上述各体系退火热处理后均可形成梯度相形态，且相间界面张力越大．高分子共混物中梯度相形态形成速度也越快     

Chemical-physical aspects of formation and evolution of phase structure in multi-polymers: Intensity fluctuation, phase structure and its fractal characteristics in blends of isotactic polypropylene with poly(cis-1,4-butadiene) rubber

This paper studies the formation and evolution of phase structure of isotactic polypropylene/poly(cis-1,4-butadiene) (iPP/PcBR) blends during molten and mixing in a visual mixer by on-line analysis of the small angle light back scattering. The density fluctuation of iPP/PcBR blends during molten and mixing is discussed using the integral-intensity Js, of the scattering intensity of the blends. The "invariant" Q, which shows fluctuation of the system, is calculated by data of the small angle light back scattering, and the variation of Q with the blending time, temperature and shear rate during molten and mixing in iPP/PcBR blends is discussed. The structure parameters which characterize dimensions of phase in the blends, as the correlation distance ac, and the average chord lengths of two-phase, as li PP and lP cBR, are calculated by data of scattering intensity. The average diameters dp of dispersed phases are calculated from SEM images. The variation of ac, dp, li PP and lP cBR with the blending time and compositions in the blends during molten and mixing is discussed. The scale law is analyzed to find multi-scale characteristics in this system. The generalized fractal dimension Dp is calculated and the relation of Dp with generalized entropy function is discussed to determine that Dp is state function and the physical significance of Dp is the same as that of the generalized entropy function.     

FRACTAL CHARACTER OF PHASE MORPHOLOGY OF HIGH IMPACT POLYSTYRENE/POLY（cis-BUTADIENE） RUBBER BLENDS

Evolution and fractal character of the phase morphology of high impact polystyrene/poly（cis-butadiene） rubber （HIPS/PcBR） blends during melting and mixing were investigated using scanning electron microscopy （SEM）. The characteristic length L was defined as the size of particles of the dispersed phase in blends. Different fractal dimensions, Df and Din, were introduced to study the distribution width of phase dimensions in the dimensionless region and the uniformity of the spatial distribution of particles, respectively. The results showed that the average characteristic length Lm and Df increase as the volume fraction of the dispersed phase increases, when the volume fraction of the dispersed phase is lower than 50%. In other words, the size of particles increases and their distribution in the dimensionless region becomes more uniform. Meanwhile, the uniformity of the spatial distribution becomes more perfect as the volume fraction increases. At a certain composition, Lm decreases in the initial stage of the mixing and levels off in the late stage. In the initial stage, Df becomes large rapidly with the process of blending, which means that the distribution of L in the dimensionless region becomes more uniform. Meanwhile, the spatial distribution tends to be ideal rapidly in the early stage and fluctuates in a definite range in the late stage of the mixing.     

小角光散射在线系统研究多相聚合物双螺杆挤出过程中的相尺寸--非相容PE/PA1010体系

利用可视化双螺杆挤出机———光散射在线采集与分析系统对不相容聚合物体系聚乙烯 尼龙 10 10(PE PA10 10 )双螺杆挤出过程进行了在线分析 .相尺寸由Debye理论中的相关距离ac,平均弦长L ,以及分散相平均直径D描述 ,给出了几种参数表征适用的范围 .由在线光散射计算出的平均弦长Lscatt、分散相平均粒径Dscatt与电镜照片计算出的平均弦长LSEM 、分散相平均粒径DSEM 作了比较 ,两者比较符合 .结果表明 ,分散相颗粒尺寸沿螺杆挤出方向逐渐变小 ;随着低组分含量 (PA10 10≤ 5 0 % )的增加 ,分散相颗粒尺寸变大 ,在组成比为 70 30和 6 0 4 0时出现双连续相     

侧链液晶离聚物对PA1010/PP共混体系的增容作用

将聚酰胺（PA1010）、聚丙烯（PP）和热致型侧链液晶离聚物（SLCI）进行熔融共混，采用FTIR，SEM，DSC，WAXD研究测定了共混物中的相互作用，用形态结构，热行为和结晶行为，系统地研究了SLCI对PA101／PP共混物的增容作用。结果表明，SLCI有效地改善了PA1010／PP共混物的形态结构，增强了PA1010与PP链间的相互作用，使PA1010／PP熔点升高，结晶度提高。     

Investigations on structure and properties of blends of polypropylene with polyamide 1010 by Rayleigh scattering

The phase structure and morphology of polypropylene （iPP） blends with poly（decamethylene sebacamide （polyamide 1010, PA 1010） and the part-compatible alloys （iPP/PA 1010/iPP-g-MAH） are investigated by Rayleigh scattering, i.e. small angle light scattering （SALS）. The structure parameters of SALS, i.e. correlation distance, ac and average chord lengths, /, are calculated. Their variation with the composition of the blends and alloys is discussed. The morphology and structure of fracture surfaces in the blends and alloys are studied by SEM images. The average diameter of dispersed phase in the blends and alloys is calculated by graph processing. The variation of average diameter is similar as that of average chord lengths of dispersed phases. The mechanical properties of the blends and alloys are analyzed and the relation of modulus and yield stress with the composition is studied. It is confirmed that the correlation between the modulus and the structure parameters is non-linear, while the correlation between the yield stress and the composition or structure parameters is linear.     

POE-g-PMAH反应性增容PA1010/PP共混物的性能研究

乙烯-辛烯共聚物-g-聚马来酸酐(POE-g-PMAH)作为反应性增容剂,采用熔体共混的方法制备了PA1010/PP共混物,通过扫描电镜(SEM)、力学性能、傅立叶变换红外光谱(FTIR)和示差扫描量热(DSC)测试,研究了POE-g-PMAH对PA1010/PP共混物的增容作用.结果表明,POE-g-PMAH的加入可以减小共混物的相区尺寸,当PA1010/PP/POE-g-PMAH=70/30/15时,分散相尺寸小而均匀;FTIR结果表明接枝在POE上的马来酸酐基团和PA1010在熔融共混期间发生了化学反应;DSC研究结果表明共混体系中PA1010和PP的结晶温度和结晶度随POE-g-PMAH的加入而降低,表明POE-g-PMAH的增容作用对PA1010和PP的结晶有抑制作用.力学性能测试结果表明随着POE-g-PMAH的增加,共混物的冲击强度逐渐增加,当POE-g-PMAH含量增加到15%时,干态冲击强度达到21.13 kJ/m2,是不加增容剂的3.1倍,而拉伸和弯曲强度可以保持较高水平.POE-g-PMAH的增容机理在于其支链中的马来酸酐能与PA1010中的胺基(NH2—)发生化学反应,而主链POE与PP有较好的亲和性,从而降低界面张力,减少相区尺寸,大幅度提高力学性能.     

Stability of the co‐continuous morphology during melt mixing for poly(ε‐caprolactone)/polystyrene blends

Over the last 10 years, research into co‐continuous polymer blends has been intense. Despite these efforts, there are very few detailed studies on the stability of this complex morphology. In this work, blends of poly(ε‐caprolactone) and polystyrene were melt‐mixed in an internal mixer for time intervals of 0.5–120 min at set temperatures of 140 and 170 °C, and the effect of the mixing time on the co‐continuous morphology was studied. This blend system was chosen because each component could be selectively dissolved and this allowed for a complete study of the co‐continuous region. The phase continuity was measured with a solvent‐extraction gravimetric technique, and the concentration range for co‐continuity was determined. The phase size and phase size distribution were obtained with the mercury intrusion porosimetry technique. The results indicate that the co‐continuous morphology forms very early in the mixing process and achieves a stable morphology within the first 5 min of mixing for virtually all the co‐continuous compositions. For all cases studied, the co‐continuous morphology remains unchanged over mixing times as long as 1–2 h. These results support the notion of a stable steady‐state formation of co‐continuous morphologies during melt mixing similar to that observed for matrix/dispersed phase type blends. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 864–872, 2007