EVOH／有机蒙脱土插层复合材料的制备与表征

将经有机化处理过的蒙脱土与EVOH熔融共混制备插层复合材料，并对该复合材料进行了XRD分析，分析结果表明：聚合物基体已经插入了有机蒙脱土片层间；复合体系中蒙脱土含量越小，蒙脱土被插开的片层间距越大；当复合体系中有机蒙脱土含量≤8％时，形成剥离型复合材料；当有机蒙脱土含量在8％～15％时，形成插层型复合材料；当有机蒙脱土含量大于15％时，复合材料中蒙脱土片层间距无明显变化。对EVOH与蒙脱土熔融共混过程的扭矩分析表明：该复合材料熔融混合9min之后，达到均匀混合和完全塑化的状态。     

环氧树脂／蒙脱土纳米复合材料的制备与剥离机理研究进展

阐述了蒙脱土的性质及其在基体树脂中的剥离机理、环氧树脂／蒙脱土纳米复合材料的制备方法。原位插层复合法是制备环氧树脂／蒙脱土纳米复合材料最常用的方法；有机改性剂、固化剂及固化条件会对蒙脱土在环氧树脂中的剥离与插层行为产生影响；环氧单体聚合过程中产生的弹性力是使蒙脱土片层发生剥离的主要原因。重点介绍了近几年来制备高度剥离型纳米复合材料的方法和工艺，指出蒙脱土在复合材料中的完全均匀剥离仍然是现阶段有待解决的关键问题。     

聚丙烯／有机蒙脱土复合材料的制备、结构及性能

以改性聚丙烯作增容剂，用熔融插层法制备了聚丙烯／有机蒙脱土复合材料，研究了有机蒙脱土对复合材料力学性能的影响，并用X射线衍射研究了复合材料的结构。结果表明：增容剂增加了聚丙烯与蒙脱土片层之间的作用力，使蒙脱土片层间距增大，在聚丙烯基体中分散更好，因而使聚丙烯／有机蒙脱土复合材料的缺口冲击强度大幅度提高，当蒙脱土含量达5％时，缺口冲击强度提高120％，并且拉伸性能下降不大，约下降5％，其中有机蒙脱土TJ4的增韧效果最好。     

HDPE／PC／相容剂／蒙脱土复合材料性能的研究

研究了HDPE／PC／增容剂／蒙脱土共混复合体系的力学性能和熔体的流变性能。结果表明，加入适量的增容剂和蒙脱土对HDPE／PC复合材料力学性能有一定的提高。在所研究的剪切应力、剪切速率、温度及组成范围内，该复合材料的lgη-lgγ曲线都偏离牛顿流体曲线，为非牛顿假塑性流体。经过有机化处理的蒙脱土复合材料体系比未经有机化处理的蒙脱土复合材料体系有更好的流动性和力学性能。     

聚氯乙烯／蒙脱土纳米复合材料的制备与性能

对钠基蒙脱土进行有机化处理,XRD表明有机阳离子已同钠离子发生离子交换。熔融法制备聚氯乙烯／蒙脱土插层复合材料,用X－射线衍射研究复合材料的结构,聚氯乙烯不能插层于钠基蒙脱土,但能插层于有机蒙脱土,形成剥离型纳米复合材料。采用DSC研究了聚氯乙烯／有机蒙脱土复合材料的玻璃化转变温度,研究结果表明,聚氯乙烯／有机蒙脱土比聚 乙烯／钠基蒙脱土复合材料的力学性能优异。     

聚苯乙烯/蒙脱土纳米复合材料的制备与表征

用十二烷基硫酸钠对钠基蒙脱土进行有机改性，将其层间距打开。用FT—IR和XRD进行表征。结果表明：有机插层剂已插层进入蒙脱土层间，然后利用乳液聚合法制备了聚苯乙烯／蒙脱土纳米复合材料。DTA和TGA分析表明：与纯聚苯乙烯相比，所得聚苯乙烯／蒙脱土(PS／MMT)纳米复合材料的热性能得到提高。     

乳液聚合法制备聚苯乙烯／蒙脱土插层复合材料

利用乳液聚合法制备了聚苯乙烯／蒙脱土插层复合材料,XRD,FTIR等表明,聚苯乙烯已插层进入蒙脱土层间,TGA,DSC表明,复合材料的热稳定性提高了,其热分解温度和玻璃化转变温度的提高是由于聚苯乙烯插层进入蒙脱土层间,并和蒙脱土产生相互作用的结果,初步提出了乳液聚合插层机理。     

原位聚合法PS／蒙脱土复合材料燃烧性能的研究

采用原位聚合法分别制备了聚苯乙烯／有机蒙脱土（PS／OMMT）复合材料和聚苯乙烯／无机蒙脱土（PS／MMT）复合材料、用锥形量热仪测量测试了复合材料的燃烧性能，结果发现复合材料的热释放速率、质量损失速率、生烟速率等均显著降低，说明复合材料具有阻燃性。通过分析材料的燃烧性能和燃烧残余物，探讨了其可能的阻燃机理。还考察了原位聚合法对聚合转化率的影响。研究表明原位聚合法制备的PS／蒙脱土复合材料是一种阻燃效能高、环境友好且实际可行的阻燃体系。     

有机插层剂对聚酰胺6／MMT纳米复合材料制备的影响研究

以烷基胺、季铵盐和氨基酸作为有机插层剂与蒙脱土片层进行阳离子交换，制备出层间距不同的有机蒙脱土。采用熔融插层法和原位聚合法分别制备聚酰胺（R％）／蒙脱土（MMT）纳米复合材料，并利用XRD、FT-IR、TEM对有机蒙脱土及纳米复合材料进行结构表征。研究结果表明：用烷基胺、季铵盐和氨基酸有机插层剂改性的蒙脱土层间距由原来的1．25nm分别增大到3．21nm、3．99nm和1．82m；季铵盐有机插层剂更适用于熔融插层法制备PA6／MMT纳米复合材料，而氨基酸有机插层剂更适用于原位聚合法制备PA6／MMT纳米复合材料。     

中国专利

正一种聚乙烯/聚苯乙烯/有机改性蒙脱土复合材料及其制备方法本发明公开了一种聚乙烯/聚苯乙烯/有机改性蒙脱土复合材料。采用Gemini表面活性剂通过插层进入蒙脱土片层,对蒙脱土片层进行有效剥离,并在超声条件下制备纳米蒙脱土;然后将有机改性蒙脱土与聚苯乙烯溶液共混,再与聚乙烯进行机械共混,制备了聚乙烯/聚苯乙烯/有机改性蒙脱土复合材料。将有机蒙脱土与聚苯乙烯溶液共混,促进其在聚乙烯/聚苯乙烯基体中的分散,通过机械共混,使聚乙烯、聚苯乙烯分子链插层进入有     

PP/PS-海泡石插层纳米复合材料的流变性能与形态结构

采用苯乙烯乳液聚合法对有机海泡石原位插层,将插层产物聚苯乙烯(PS)-海泡石与聚丙烯(PP)熔融共混制备PP/PS-海泡石插层纳米复合材料.流变测试结果表明:PP/PS-海泡石插层纳米复合材料为典型的假塑性流体,其偏离牛顿流体的程度随PS-海泡石含量增加而增大,表观黏度和零切黏度随着PS-海泡石含量的增加而减小,PS-...     

SEP和蒙脱土复合增强PP／PS合金的研究

观察了聚丙烯(PP)/聚苯乙烯(PS)／(苯乙烯-乙烯/丙烯二嵌段共聚物)(SEP)合金的形态，测定了SEP、SEP/改性蒙脱土复合材料对PP／PS合金的力学性能的影响。结果表明：SEP在EPP／PS合金中作为增容剂，减小了分散相的平均粒子尺寸，大大改变了合金的形态，增强了两相间的粘合力，提高了合金的力学性能，并对PP/PS(20／80)合金的增容作用较为显著。结果还表明：SEP／改性蒙脱土复合材料对PP／PS(20／80)合金具有增韧增强的效果。     

聚丙烯/聚苯乙烯/超支化聚酰胺酯共混物及其纤维性能

以原位悬浮聚合法制备聚苯乙烯/超支化聚酰胺酯(PS/HBP)复合粒子,通过双螺杆共混挤出制备系列聚丙烯(PP)/PS/HBP三元共混物。运用傅里叶变换红外光谱仪对PS/HBP复合粒子进行分析,以偏光显微镜、差示扫描量热仪和锥板流变仪等仪器研究了PP/PS/HBP共混体系的相容性、聚集态结构、结晶性和流变性等性能,以万能材料试验机、红外染色机和电脑测色仪研究纤维的力学性能和染色性能。结果表明:PP、PS为热力学不相容体系,少量HBP的加入即可改变PP球晶结构,使球晶小而密,同时PS均匀分散在PP中;引入HBP使得PP的结晶结构有所完善,结晶温度和结晶度升高;引入PS/HBP复合粒子对PP纤维可纺性影响不大,表现为结构化黏度指数轻微升高,但共混纤维可拉伸性较纯PP有极大提高,力学性能有明显改善,染色性能也有显著提高。     

PP／PS／SEBS三元共混物的研究

以PS、SEBS为改性剂对PP进行改性。加入PS,体系的强度和刚度得到提高,断裂伸长率和冲击性能下降,对其改变的原因采用SEM进行了结构分析;SEBS是PS的良好相容剂,也是PP很好的增韧剂。同时使用PS和SEBS,体系拉伸强度为24．4MPa,弯曲模量810．6MPa,冲击强度82．0J／m,熔体流动速率12．7g/10min。     

Glass transition behavior of polypropylene/polystyrene/styrene-ethylene-propylene block copolymer blends

Summary The glass transition behavior of ternary blends of polypropylene (PP), polystyrene (PS) and styrene-ethylene-propylene-styrene block copolymer (SEPS) was investigated. The blends were prepared by an internal mixer, and their dynamic mechanical properties and morphology were measured. The blends showed phase inversion at around 75wt% PS composition. The glass transition temperature (T_g) of the PP phase shifted to lower temperature as the PS contents were increased in PP/PS binary blends, probably due to the mismatch of thermal expansion coefficients between two components. As the SEPS copolymer contents were increased, the T_g's of the PP phase in the blends increased. In particular, the large increase in T_g of the PP phase was observed in the PP/PS (25/75) blends where the phase inversion takes place. Received: 2 February 1998/Revised version: 24 March 1998/Accepted: 13 April 1998     

关于PS/PP系共混物的研究——第1报 PS/PP共混体系的相容性和相态结构

本研究以苯乙烯—乙烯—丁烯—苯乙烯嵌段共聚物(SEBS)和苯乙烯—乙烯—丙烯嵌段共聚物(SEP)为界面活性剂(相溶化剂),研究聚苯乙烯等规聚丙烯(PS/PP)共混体系的相容性;研究PS/PP两成分体系和添加界面活性剂后三成分体系的相态结构及相界面形态。为制取结构稳定的PS/PP系共混物,进一步制取具有特殊性能约PS/PP共混纤维提供实用的工艺条件和理论依据。     

PE/PP/PS反应性共混研究

研究了无水AlCl₃在PE/PP/PS共混过程中的反应性作用,考察了无水AlCl₃用量对PE/PP/PS合金力学性能和PP结晶行为的影响。结果表明:在PE/PP/PS共混过程中加入适量的无水AlCl₃,可以起到有效的增容作用,提高了合金的力学性能。     

Nonisothermal crystallization kinetics of polypropylene/polypropylene‐g‐polystyrene/polystyrene blends

The nonisothermal crystallization kinetics of polypropylene (PP), PP/polystyrene (PS), and PP/PP‐g‐PS/PS blends were investigated with differential scanning calorimetry at different cooling rates. The Jeziorny modified Avrami equation, Ozawa method, and Mo method were used to describe the crystallization kinetics for all of the samples. The kinetics parameters, including the half‐time of crystallization, the peak crystallization temperature, the Avrami exponent, the kinetic crystallization rate constant, the crystallization activation energy, and the F(T) and a parameters were determined. All of the results clearly indicate that the PP‐g‐PS copolymer accelerated the crystallization rate of the PP component in the PP/PP‐g‐PS/PS blends. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

In situ compatibilization of polypropylene/polystyrene blend by controlled degradation and reactive extrusion

In situ compatibilization of polypropylene (PP) and polystyrene (PS) was achieved by combinative application of tetraethyl thiuram disulfide (TETD) as degradation inhibitor and di‐tert‐butyl peroxide as degradation initiator in the process of reactive extrusion. The PP/PS blends obtained were systematically investigated by rheological measurement, scanning electron microscopy, and differential scanning calorimetry. The results indicate that peroxide‐induced degradation of PP can be effectively depressed by adding TETD, which may favor the formation of PP‐g‐PS copolymer during melt processing. The PP‐g‐PS copolymer formed may act as an in situ compatibilizer for PP/PS blends, and subsequently decreases the size of dispersed PS phase and changes both rheological and thermal properties of the blends. Based on the present experimental results, the mechanisms for the controlled degradation of PP and in situ formation of PP‐g‐PS copolymer in the PP/PS blends have been proposed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Compatibilization of polypropylene/polystyrene blends with poly(styrene-b-butadiene-b-styrene) block copolymer

The compatibilizing effect of the triblock copolymer poly(styrene-b-butadiene-b-styrene) (SBS) on the morphology and mechanical properties of immiscible polypropylene/polystyrene (PP/PS) blends were studied. Blends with three different weight ratios of PP and PS were prepared and three different concentrations of SBS were used for investigations of its compatibilizing effects. Scanning electron microscopy (SEM) showed that SBS reduced the diameter of the PS-dispersed particles as well as improved the adhesion between the matrix and the dispersed phase. Transmission electron microscopy (TEM) revealed that in the PP matrix dispersed particles were complex “honeycomblike” aggregates of PS particles enveloped and joined together with the SBS compatibilizer. Wide-angle X-ray diffraction (WAXD) analysis showed that the degree of crystallinity of PP/PS/SBS slightly exceeded the values given by the addition rule. At the same time, addition of SBS to pure PP and to PP/PS blends changed the orientation parameters A₁₁₀ and C significantly, indicating an obvious SBS influence on the crystallization process in the PP matrix. SBS interactions with PP and PS influenced the mechanical properties of the compatibilized PP/PS/SBS blends. Addition of SBS decreased the yield stress and the Young's modulus and improved the elongation at yield as well as the notched impact strength in comparison to the binary PP/PS blends. Some theoretical models for the determination of the Young's modulus of binary PP/PS blends were used for comparison with the experimental results. The experimental line was closest to the series model line. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 69: 2625–2639, 1998