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Ti(On-Bu)4/AlEt3-Et(Ind)2ZrCl2/MAO催化体系原位聚合制备LLDPE  [PDF]
柳忠阳,徐德民,王军,郭存悦,贺大为,胡友良
科学通报 , 2001,
Abstract: 利用茂金属与MAO的复合物为乙烯原位聚合制备短链支化聚乙烯的共聚催化剂,以Ti(On-Bu)4/AlEt3为二聚催化剂组成双功能催化剂体系,该聚合体系具有高活性、分子量分布窄、结晶度低以及聚合物物性可调等优异特点.
(2-Me-3-ClPh)2PBIMe2FeCl2racC2H4(Ind)2ZrCl2/MAO双功能催化体系乙烯原位共聚制备LLDPE  [PDF]
王如义,郑元锁,崔楠楠,张志成,柯毓才,胡友良
高分子学报 , 2005,
Abstract: 合成了后过渡金属铁(2Me3ClPh)2PBIMe2FeCl2低聚催化剂,并与亚乙基桥茂金属共聚催化剂racC2H4(Ind)2ZrCl2共用,用MAO(1.4mol/L甲苯溶液)作为助催化剂,原位共聚合成线性低密度聚乙烯(LLDPE).结果发现,这种后过渡铁催化剂具有很高的低聚催化活性[10×107goligomer(molFe·h)],双功能催化体系的催化活性保持在106gPE(molFe·h)以上;13C-NMR分析表明,得到了线性低密度聚乙烯,当Fe-Zr比为1/2时,也没有出现α-烯烃残留现象,说明这两种催化剂具有好的匹配性;随Fe-Zr比和反应温度的变化,聚合物的熔点、结晶度、熔点等均表现出很好的规律性.
Comparative study of the morphology and properties of PP/LLDPE/wood powder and MAPP/LLDPE/wood powder polymer blend composites
eXPRESS Polymer Letters , 2010, DOI: 10.3144/expresspolymlett.2010.88
Abstract: In this study, polypropylene (PP)/linear low-density polyethylene (LLDPE) and maleic anhydride grafted polypropylene (MAPP)/LLDPE blend systems were comparatively investigated. The blends and composites contained equal amounts of the two polymers, and the compatibility and miscibility between the two polymers were investigated. Composites with 10, 20 and 30 wt% wood powder (WP), but still with equal amounts of the two polymers, were prepared and investigated. The morphologies, as well as mechanical and thermal properties, of the blends and the blend composites were investigated. The MAPP/LLDPE blend and composites showed better properties than the PP/LLDPE blend and composites as a result of the stronger interfacial interaction between MAPP, LLDPE and WP. The SEM and DSC results of the PP/LLDPE/WP blend composites showed that WP located itself more in the LLDPE phase. In the MAPP/LLDPE/WP composites the WP was in contact with both polymers, although it had a greater affinity for MAPP. The TGA results show that the MAPP/LLDPE blend and composites are more thermally stable than the PP/LLDPE blend and composites.
Mechanical properties and thermal behaviour of LLDPE/MWNTs nanocomposites
Jin-hua, Tai;Guo-qin, Liu;Huang, Caiyi;Lin-jian, Shangguan;
Materials Research , 2012, DOI: 10.1590/S1516-14392012005000122
Abstract: multi-walled carbon nanotubes (mwnts) were incorporated into a linear low-density polyethylene (lldpe) matrix through using screw extrusion and injection technique. the effect of different weight percent loadings of mwnts on the morphology, mechanical, and thermal of lldpe/mwnts nanocomposite had been investigated. it was found that, at low concentration of mwnts, it could uniformly disperse into a linear low-density polyethylene matrix and provide lldpe/mwnts nanocomposites much improved mechanical properties. thermal analysis showed that a clear improvement of thermal stability for lldpe/mwnts nanocomposites increased with increasing mwnts content.
蒙脱土负载聚合催化剂用于乙烯原位共聚制备LLDPE  [PDF]
张志成,王如义,柯毓才,郑元锁,郭存悦,崔楠楠,胡友良
高分子学报 , 2004,
Abstract: 将蒙脱土(MMT)负载的聚合催化剂rac-Et(Ind)2ZrCl2和均相低聚催化剂{[(2ArNC(Me))2C5H3N]FeCl2}(Ar=2,4C6H4(Me)2)组成双功能催化体系用于乙烯原位共聚制备线性低密度聚乙烯(LLDPE).通过调节两种催化剂之间的比例和MAO的用量制备了一系列支化度不同的LLDPE产品.聚合反应动力学曲线表明,两种催化剂表现出各自的乙烯吸收特征,蒙脱土负载化的共聚催化剂催化乙烯聚合时反应平稳易控制.DSC曲线表明,聚合物的熔点和结晶度随Fe/Zr的增大而减小.用密度梯度法测得的聚合物密度随Fe/Zr的增大而降低.从13C-NMR谱图上可以看到,得到的聚合物是LLDPE,其支化度随Fe/Zr的增大而增大,聚合物中仍含有未共聚的α-烯烃,这一点从GPC上也能得到验证.扫描电镜(SEM)照片表明用这种双功能催化剂共聚得到的LLDPE具有良好的形态.
球形MgCl2负载的MAO/rac-Et[Ind]2ZrCl2催化剂催化丙烯聚合  [PDF]
关吉吉,郑莹,焦书科
化学学报 , 2001,
Abstract: 采用只在球形MgCl2上负载MAO,聚合前再同rac--Et[Ind]2ZrCl2预混的负载方式进行丙烯聚合。在少量AlEt3的活化下,很低的Al(MAO)/Zr摩尔比时即可获得比均相催化剂高一个数量级的活性,考察了温度、压力、Al(MAO)/Zr摩尔比和催化剂浓度对聚合的影响,同时用13^CNMR测定了均相和载体催化体系所制备的聚丙烯的微结构,发现负载型茂金属催化剂制得的聚丙烯立构规整性高于均相体系,其五元组立构序列[mmmm]可从均相的52.6%提高到负载催化剂的79.5%。扫描电镜观察表明,聚合物颗粒可较好地复制球形催化剂的颗粒形态。
EPITAXIAL CRYSTALLIZATION IN HIGHLY ORIENTED LLDPE/IPP BLEND
LLDPE/IPP共混物高取向薄膜的附生结晶

ZHANG Wei-guang,YANG De-cai,
张伟广
,杨德才

高分子学报 , 1992,
Abstract: 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.
Mao the peoples Emperor, Hutchinson, 1979,  [cached]
J.C. Boshoff
Scientia Militaria : South African Journal of Military Studies , 2012, DOI: 10.5787/14-4-512
Abstract: Dick Wilson has written a detailed account of Mao Tse Tung's life, from his beginnings as a peasant's son, to the day he entered Peking to proclaim to China and to the world the beginning of a new order.
气相法LLDPE催化剂(MgCl2/TiCl4.THF/AlEt3)结构的红外光谱研究  [PDF]
杨新源,陈念劬,饶国瑛
催化学报 , 1984,
Abstract: ?
EAA增容LLDPE/PEO共混物及其增容机理  [PDF]
徐胜清,唐涛,黄葆同,殷翠梅
化学学报 , 1998,
Abstract: 以乙烯-丙烯酸共聚物(EAA)为增容剂,研究了它在线性低密度聚乙烯(LLDPE)/聚环氧乙烷(PEO)共混物中的增容作用及其增容机理。采用电子显微镜(SEM)、动态力学分析(DMA)、DSC和红外光谱(IR)对共混物形态及其微观结构进行了表征。结果表明,EAA对LLDPE/PEO共混物有一定的增容作用;其增容机理为EAA和LLDPE两者的非晶区部分相容,而EAA分子中的羧基与PEO分子中的醚氧基相互作用形成了分子间氢键。
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