聚酰胺1010／聚乙烯－马来酸酐接枝共聚物共混物力学和热学性能研究

为了表明马来酸酐接枝聚烯烃后对聚酰胺的相容作用，本文研究了聚酰胺１０１０（ＰＡ１０１０）／聚乙烯－马来酸酐接枝共聚物（ＰＥ－ｇ－ＭＡＨ）共混物在不同ＭＡＨ接枝量下的结晶性与力学性能。研究表明，ＭＡＨ的存在导致ＰＥ－ｇ－ＭＡＨ－ｃｏ－ＰＡ１０１０共聚物的形成，而该共聚物在标题共混物中起着相容剂的作用。共混物的结晶性能变化显示了共混组分间存在一定程度的混溶性。在一定的ＭＡＨ含量内，标题共混物具有协同效应。     

固相法氯化聚乙烯增韧聚氯乙烯的研究

研究了聚氯乙烯与固相法氯化聚乙烯的相容性与氯含量、共混方式以及ＣＰＥ链结构的关系，动态力学性能表明ＰＶＣ／ＣＰＥ为部分相容体系，ＣＰＥ中类似ＰＶＣ的链段与ＰＶＣ形成相间过渡层，共混方式影响共混体系的相容程度，透射电镜结构表明ＣＰＥ呈连续网络结构分布于ＰＶＣ粒子表面，共混条件一定时，共混物的抗张强度随相容性的改改善而增加。     

高密度聚乙烯与乙烯丙烯辛烯－1共聚物共混体系的相容性

用ＤＳＣ和ＷＡＸＤ方法研究了高密度聚乙烯／聚（乙烯丙烯辛烯－１）（ＨＤＰＥ／ＥＰＯ）共混体系的结晶性能。共混物的ＤＳＣ曲线皆呈单峰，表明共混体系形成了共晶。晶胞参数ａ及结晶度随共混物组成而变，进一步证明ＨＤＰＥ／ＥＰＯ共混体系的相容性．     

高密度聚乙烯与乙烯丙烯辛烯—1共聚物共混体系的相容性

用ＤＳＣ和ＷＡＸＤ方法研究了高密度聚乙烯／聚（乙烯丙烯辛烯－１）（ＨＤＰＥ／ＥＰＯ）共混体系的结晶性能。共混物的ＤＳＣ曲线皆呈单峰，表明共混体系形成了共晶。晶胞参数ａ及结晶度随共混物组成而变，进一步证明ＨＤＰＥ／ＥＰＯ共混体系的相容性。     

EVA增容PP/HDPE共混体系的形态结构与性能

采用乙烯－醋酸乙烯酯共聚物（ＥＶＡ）作为聚丙烯（ＰＰ）／高密度聚乙烯（ＨＤＰＥ）共混体系的增容剂,通过冲击实验、拉伸实验、示差量热扫描仪（ＤＳＣ）和扫描电镜（ＳＥＭ）,系统地研究了共混体系的性能与其形态结构之间的。结果表明,ＥＶＡ是ＰＰ／ＨＤＰＥ共混物较好物增容剂,ＥＶＡ可以使ＰＰ、ＨＤＰＥ的晶相结构受到一定程度的破坏,增加ＰＰ和ＨＤＰＥ的相容性,同时共混物的冲击韧性明显提高。     

聚丙烯／氯化聚乙烯共混物的形态结构

用透射电子显微镜方法研究了聚丙烯（ｉＰＰ）和氯化聚乙烯（ＣＰＥ）共混物溶液浇铸膜的形态结构．共混物中ＣＰＥ含量≤７０％时不妨碍ｉＰＰ球晶两种结构（交叉结构和条状结构）区域的生成．在ＣＰＥ含量≥８０％时，分散相ｉＰＰ形成近乎直角（８０°）交叉的稀疏的片晶网络．在共混物的全组成范围内，ＣＰＥ结晶在ｉＰＰ片晶上附生生长，二者结晶Ｃ轴的交角为５０°     

聚丙烯／氯化聚乙烯共混物的形态结构

 用透射电子显微镜方法研究了聚丙烯（ｉＰＰ）和氯化聚乙烯（ＣＰＥ）共混物溶液浇铸膜的形态结构．共混物中ＣＰＥ含量≤７０％时不妨碍ｉＰＰ球晶两种结构（交叉结构和条状结构）区域的生成．在ＣＰＥ含量≥８０％时，分散相ｉＰＰ形成近乎直角（８０°）交叉的稀疏的片晶网络．在共混物的全组成范围内，ＣＰＥ结晶在ｉＰＰ片晶上附生生长，二者结晶Ｃ轴的交角为５０°     

含二烯丙基双酚A醚相容剂对HDPE/PC共混体系的影响

用低密度聚乙烯接枝二烯丙基双酚Ａ醚（ＬＤＰＥ ｇ ＤＢＡＥ）作为高密度聚乙烯／聚碳酸酯（ＨＤＰＥ／ＰＣ）共混体系的增容剂,研究了其对ＨＤＰＥ／ＰＣ共混体系的影响．通过共混物形态观察、热力学性能测试和结晶性分析,发现ＬＤＰＥ ｇ ＤＢＡＥ对ＨＤＰＥ／ＰＣ共混体系有良好的增容效果．并发现了增容剂在共混物中的最佳用量为１０ｐｈｒ,提高增容剂的接枝率更有利于改善共混物的性能     

聚酰胺1010／聚乙烯—马来酸酐接枝共聚物共混物力学和热学性能研究

为了表明马来酸酐接枝聚烯烃后对聚酰胺的相容作用，本文研究了聚酰胺１０１０／聚乙烯－马来酸酐接枝共聚物 共混物在不同ＭＡＨ接枝量下的结晶性与力学性能。在一定的ＭＡＨ含量内，标题共混物 具有协同效应。     

聚乙烯串晶在单轴拉伸形变过程中的微结构变化和机理

本文采用电子显微镜和小角Ｘ－射线散射（ＳＡＸＳ）技术研究了含有串晶结构（Ｓｈｉｓｈ—ｋｅｂａｂ）的高密度聚乙烯（ＨＤＰＥ）／超高分子量聚乙烯（ＵＨＭＷＰＥ）共混物高取向膜在单轴拉伸过程中的微结构变化．深入探讨了拉伸温度对聚乙烯在形变过程中微结构变化的影响．室温拉伸时，聚乙烯串晶结构主要发生了解结晶过程；高温（１１５℃）形变时，主要表现为折叠链片晶直接转变为伸展链纤维晶的应变诱导结晶过程．     

高密度聚乙烯／超高分子量聚乙烯共混物高取向薄膜形态结构与力学性能的研究

he morphology and properties of highly oriented films of blends ofHDPE/ UHMWPE were investigated by electron microscope, DSC and mechnicalproperty measurements. The as-drawn films of HDPE consist of highly oriented lamellar structure.The lamellar growing direchon is vertical to the drawing direction. AddingUHMWPE into HDPE results in formation of fibrous crystals with their fibrousaxis directions parallel to the drawing direction. The number of the fibers in thefilms of the blends increases with the increase of the content of UHMWPE. The presence of ultra - high molecular weight component in as - drawn blends films results in the increase of tensile modulus considerably.     

HDPE,LLDPE或LDPE高取向薄膜微结构的电子显微学研究

木工作用透射电子显微术及电子衍射技术研究3种PE(HDPE,LLDPE或LDPE)均聚物高取向薄膜的微结构。定量测定了它们的结晶尺寸。通过倾斜样品电子显微学研究确定了不同种PE纤维结构的对称性。     

LLDPE/IPP共混物高取向薄膜的附生结晶

本文用透射电子显微术、电子衍射等方法研究了线性低密度聚乙烯(LLDPE)和等规聚丙烯(IPP)共混物高取向薄膜的形态结构.在熔体拉伸薄膜中统组分的LLDPE与IPP均以高取向的片晶形式存在,片晶生长方向垂直手拉伸方向.当共混物中LLDPE含量较低(小于40％)时,作为分散相的LLDPE在IPP上附生结晶.两种片晶的c轴成45°交角,附生结晶的接触面为LLDPE的(100)和IPP的(010).而在LLDPE含量大于50％时,LLDPE形成独立的相区,则不存在附生结晶现象,结果两种片晶的生长方向均垂直于拉伸方向.在135℃热处理15min,然后自然冷却的LLDPE/IPP共混物薄膜中,当LLDPE含量≤50％时,LLDPE仍然在IPP上附生生长,二者的结构关系与热处理前的相同.     

聚丙烯/高密度聚乙烯高取向共混物的附生结晶

<正> 最近,聚合物之间的附生结晶引起人们的极大兴趣和关注。附生结晶是一种结晶物质在另一种结晶物质上的取向生长,二者之间有特殊的作用。这种附生作用对结晶聚合物共混体系的形态结构和性能有极为重要的影响。本工作以电子显微镜方法研究熔体拉伸直接导致等规聚丙烯(iPP)和高密度聚乙烯(HDPE)共混物附生结晶。     

预热处理对超高分子量聚乙烯层积状片晶凝胶膜结构的影响

由准稀溶液速冷制备的超高分子量聚乙烯（ＵＨＭＷＰＥ）凝胶膜，具有片晶（Ｌａｍｅｌｌａ）取向平行于膜面的层积状结构，在１２９—１３４℃的温度范围内拉伸，可获得超高拉伸比（λ＞２００）．通过ＩＲ及Ｘ－ｒａｙ衍射等方法研究发现，拉伸前用不同温度退火处理后，凝胶膜的片晶微结构产生明显变化，在对应于超高拉伸温度范围内，其结晶度增加，微晶的ｃ和ｂ轴方向尺寸变大，而ａ轴方向的尺寸减小，从理论上对这一变化过程作了考察，并讨论了超高拉伸取向性与这些结构变化的关系以及可超拉伸取向性的最佳温度范围．     

Morphological and structural features of heat-treated drawn polypropylene/high-density polyethylene blends

The ion etching technique has been applied to a morphological study of mechanically blended polypropylene (PP) with high-density polyethylene (HDPE). Samples blended to PP/HDPE compositions of 65/35 and 85/15 by weight were highly drawn and then heat treated for 30 min at selected temperatures up to 163°C. When these samples are carefully ion-etched several features are observed in electron micrographs, namely (i) crosshatched, and (ii) twisted or layered textured inclusions of HDPE crystals within arrays of lamellalike PP crystals situated perpendicular to the direction of drawing. X-ray diffraction measurements of the drawn samples heat treated in the range 145–163°C for 30 min shows that oriented HDPE crystallizes with b-axis orientation along the drawing direction. Supporting evidence is obtained from electron diffraction measurements. The molecular weight of the HDPE component is a major factor in the b-axis-oriented growth of HDPE crystals in PP/HDPE blends.     

Unexpected molecular weight dependence of shish-kebab structure in the oriented linear low density polyethylene/high density polyethylene blends

In this study, highly oriented shish-kebab structure was achieved via imposing oscillatory shear on the melts of linear low density polyethylene (LLDPE)/high density polyethylene (HDPE) blends during the packing stage of injection molding. To investigate the effect of molecular weight of HDPE on the formation of shish-kebab structure, two kinds HDPE with large melt flow index (low molecular weight) and small melt flow index (high molecular weight) were added into LLDPE matrix. The structural characteristics of LLDPE/HDPE blends were systematically elucidated through two-dimensional wide-angle x-ray scattering, scanning electron microscopy, and differential scanning calorimetry. Interestingly, an unexpected molecular weight dependence of shish-kebab structure of the prepared samples was found that the addition of HDPE with low molecular weight resulted in an higher degree of orientation, better regularity of lamellar arrangement, thicker lamellar size, and higher crystal melting temperature than that adding HDPE with high molecular weight. Correspondingly, the blend containing low molecular weight HDPE had better tensile strength. A possible mechanism was suggested to elucidate the role of HDPE molecular weight on the formation of shish-kebab structure in the oriented blends, considering the change of chain mobility and entanglement density with change of molecular weight.     

左旋聚乳酸/聚(ε-己内酯)共混物在取向聚乙烯基底上的附生结晶行为

利用电子显微镜结合电子衍射研究了左旋聚乳酸/聚(ε-己内酯)(PLLA/PCL)共混物在取向聚乙烯(PE)基底上的结晶行为.纯PLLA在取向PE基底上能够附生结晶,主要形成分子链相互垂直的片晶结构.PCL在PE基质上也能发生附生结晶,导致两者分子链平行.PLLA/PCL共混物在取向PE基底上结晶的形态结构依赖于共混组成.在PLLA含量大于95 wt%时,PCL不影响PLLA与PE的附生结晶行为.当PCL含量增加至10 wt%时,PLLA在PE上的附生结晶行为受到了一定程度的影响.当PCL含量超过40 wt%时,PLLA在PE上的附生结晶被抑制,取而代之是PCL在PE取向基质上附生结晶,产生两者分子链平行的取向片晶.另外,在PLLA含量在50 wt%~30 wt%之间时,体系产生明显的微相分离,微相分离并不影响PCL与PE的附生结晶,在PCL的富集区仍然发生平行链附生结晶,而PLLA的富集区结构变得模糊.当PLLA含量少于20 wt%时,微相分离不明显,少量PLLA应该分散在PCL片晶间的非晶区.     

On the crystallization of syndiotactic polypropylene (sPP)/high density polyethylene (HDPE) blends

 The crystallization kinetics of syndiotactic polypropylene (sPP)/high-density polyethylene (HDPE) blends were investigated by thermal and microscopical methods. Isothermal crystallization obtained by differential scanning calorimetry (DSC) was used to study the nucleation ability of HDPE on sPP crystallization. Morphological studies with polarized light microscopy (PLM) of solution cast films resulted in a transcrystalline-like overgrowth of the sPP on HDPE spherulites. The arrangement of the HDPE lamellar crystals in the blend were observed in transmission electron microscopy (TEM). But from these results, no straightforward conclusion about the transcrystalline nature of the sPP crystals can be given. Received: 24 November 1997 Accepted: 23 February 1998