低温合成高等规度聚1-丁烯

考察了低温聚合下三乙基铝/负载钛高效催化剂[n(Al)/n(Ti)]、n(Ti)/1-丁烯[n(Bt)]、二苯基二甲氧基硅烷[n(DDS)]/n(Ti)和氢气压力对聚1-丁烯等规度和特性黏数的影响,并用差示扫描量热仪和偏光显微镜对自制试样和日本三井化学公司的试样进行了分析比较.结果表明,当n(DDs)/n(Ti)为13.21、n(Ti)/n(Bt)为3×10-5、n(Al)/n(Ti)为200、温度为15℃及氢气压力为0.02 MPa时可以合成等规度为97.2%、特性黏数为254 mL/g的聚1-丁烯.自制试样和三井化学公司试样的熔点与熔限温度范围基本一致,二者的结晶度分别为63.90%和82.96%.二种试样均为球晶,粒径分布比较均匀,但自制试样的晶粒明显大于三井化学公司的试样.自制试样的密度、硬度、冲击强度、弯曲模量及屈服强度都低于三井化学公司的试样,而拉伸强度和扯断伸长率却高于后者,这主要是在自制试样中未添加成核剂的缘故.限温度范围基本一致,二者的结晶度分别为63.90%和82.96%.二种试样均为球晶,粒径分布比较均匀,但自制试样的晶粒明显大于三井化学公司的试样.自制试样的密度、硬度、冲击强度、弯曲模量及屈服强度都低于三井化学公司的试样,而拉伸强度和扯断伸长率却高于后者,这主要是在自制试样中未添加成核剂的缘故.     

聚丁烯-1分子结构对结晶的影响

通过差示扫描量热测试法和偏光显微镜,研究了相对分子质量和等规度分别对聚丁烯-1（i-PB）结晶度和结晶形态的影响。实验结果表明：在常温结晶时若i-PB的相对分子质量越小则结晶度越高,晶粒完善性越好;同时等规度越高则结晶度越高,晶粒完善性越好。     

负载钛催化体系催化合成低相对分子质量聚丁烯-1

以氢气为相对分子质量调节剂,采用自制的TiCl4/MgCl2-Al（i-Bu）3负载钛催化体系,合成了聚丁烯-1热塑性弹性体（PBt-TPE）。在3L釜中考察了Al/Ti、Ti/Bt、氢气压力及聚合温度对单体转化率、相对分子质量、乙醚中不溶物含量及结晶度的影响。结果表明：氢气压力能够有效调节聚合物的相对分子质量,随聚合温度的升高,聚合物转化率和相对分子质量先升高后降低;乙醚中不溶物含量呈降低趋势。     

聚丁烯-1技术研究进展

本文叙述了聚丁烯-1树脂的综合性能.详细分析了国内外聚丁烯-1合成工艺及催化剂研究进展.目前世界上国外有巴塞尔和日本三井两家公司已经工业化生产聚丁烯-1树脂,均采用Ziegler-Natta催化剂.国内则没有聚丁烯-1工业生产装置,只有2万吨/年聚丙烯装置试生产聚丁烯-1.文章最后对聚丁烯-1树脂特性及聚丁烯发展潜力做以简单分析.     

聚丁烯-1改性的研究进展

综述了近年来国内外在聚丁烯-1改性尤其是加快其晶型转变速率方面的研究进展,总结并归纳了聚丁烯-1的改性方法,最后对聚丁烯-1改性领域的发展方向进行了展望.     

聚丁烯－1技术进展

介绍了国内外聚丁烯－1技术现状，包括聚丁烯－1的Z—N催化剂和茂金属催化剂研究进展，以及聚丁烯－1生产工艺技术．并简要说明了我国聚丁烯－1树脂具有很大的开发潜力。     

聚丁烯-1技术研究进展及其特性分析

叙述了聚丁烯-1树脂的综合性能,介绍了聚丁烯-1原料的现状;详细分析了国内外聚丁烯-1合成工艺及催化剂研究进展,并对聚丁烯-1树脂特性做了简单的分析。     

等规聚丁烯-1/玉米秸秆复合材料的制备与性能研究

使用硅烷偶联剂γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)改性生物质废弃物玉米秸秆粉(CP),以期改善其与聚合物的相容性,并将其引入等规聚丁烯-1(iPB)基体中制备iPB/CP复合材料,考察了改性前后复合材料的力学性能、热变形温度及微观形貌.结果表明,KH570成功的接枝到CP表面,经过KH570改性后的复合材料...     

聚丁烯-1的应用及技术进展

介绍了聚丁烯-1树脂的性能、使用现状以及相关的生产技术等。     

国内外聚丁烯-1的研究进展

文章介绍了国内外在聚丁烯-1的基本性能、结晶结构及其影响因素(温度、全同含量、分子量、CO2等)方面的研究进展;还介绍了聚丁烯-1与聚丙烯、聚乙烯的共混性能以及聚丁烯-1的老化性能和发泡工艺等。     

Tailoring the rigid amorphous fraction of isotactic polybutene-1 by ethylene chain defects

The effect of different amounts of ethylene co-units in the butene-1 chain, on the fold-surface structure of crystals of isotactic polybutene-1, has been probed by analysis of the rigid amorphous fraction (RAF). The exclusion of ethylene co-units from crystallization in random butene-1/ethylene copolymers and their accumulation at the crystal basal planes leads to a distinct increase of the RAF with increasing concentration of co-units. A specific RAF was determined by normalization of the RAF to the crystal fraction. While in the butene-1 homopolymer a specific RAF of 20–30% is detected, it increases to more than 100% in copolymers with 5–10 mol% of ethylene co-units, being in accordance with the previously observed increase of the free energy of the crystal fold-surface due to copolymerization. It has also been shown that the specific RAF increases with decreasing temperature of crystallization, due to formation of a fold-surface of lower perfection, containing an increased number of chain segments traversing the crystalline-amorphous interface.     

Effect of pressure on the melting and crystallization behaviour of isotactic polybutene-1

The formation, melting and phase transition of isotactic polybutene-1 under high hydrostatic pressures were studied by high-pressure d.t.a. and X-ray diffraction up to 5 kbar. The d.t.a. thermogram of melting of form I shows a single endothermic peak up to 5 kbar. Form II crystallized directly from the melt at atmospheric pressure is metastable and it transforms to form I by the application of pressure. Above 900 bar, it transforms to form I completely and the endothermic peak of melting of form II is not observed. On crystallization from the melt under high pressure, the percentage content of form I' increases with crystallization pressure and at 1.6 kbar only form I' is crystallized. Above 2 kbar form II', which shows the same X-ray diffraction pattern as form II, is crystallized from the melt. The percentage content of form II' increases with pressure above 2 kbar, and that of form I' decreases up to 5 kbar. Upon heating under high pressure above 2 kbar, a solid-solid transition from form II' to form I' is observed in d.t.a. traces and the transition is confirmed by high-pressure X-ray diffraction. The melting temperature is expressed in the form of a quadratic equation as a function of pressure for four different forms in IPB-1.     

Preparation of high isotactic polybutene‐1

Polymerization of butene‐1 (B‐1) was carried out with a PP‐TiCl₃/Et₂AlCl/methyl methacrylate (MMA) catalyst system in n‐heptane. The influence of temperature, pressure, time and H₂ on molecular weight, isotacticity, and catalytic activity were studied by viscometry, solubility in boiling diethyl ether, and measuring the polymer produced, respectively. The structural properties of the isotactic polybutene‐1 (IPB‐1) were characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and melt flow index (MFI). The molecular weight of the products can be controlled by H₂. It was found that the catalyst showed high isotacticity and activity. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 2533–2539, 2000     

Polymorphism of isotactic polybutene-1 as revealed by microindentation hardness. Part II: correlations to microstructure

The influence of polymorphism on the micromechanical properties of isotactic polybutene-1 (iPBu-1) has been investigated by means of the microhardness technique. Hardness data, H, of form I (hexagonal) are shown to be notably larger than those of form II (tetragonal). The H values of both polymorphic forms are shown to depend on the molecular weight, M_w, and the crystallization temperature, T_c. The hardness behaviour with M_w and T_c has been correlated to the changes of degree of crystallinity and nanostructure as derived from small angle X-ray scattering. The hardness values for iPBu-1 infinitely thick crystals (H_c^∞), of forms I and II, have been calculated for the first time. H_c^∞ of form I is shown to be notably larger than that of form II. This result is a consequence of the denser packing of the hexagonal crystal modification, and accounts for the large difference in H values found for forms I and II. Finally, the variation of the mechanical b-parameter, proportional to the surface-free energy of the crystals, with molecular weight is discussed.     

Crystalline transformation of isotactic polybutene-1 in supercritical CO2 studied by in-situ fourier transform infrared spectroscopy

The solid-solid crystalline transformation of isotactic polybutene-1 (iPB-1) from tetragonal form II to hexagonal form I could be accelerated by supercritical carbon dioxide (scCO₂). In this study, in-situ Fourier transform infrared spectroscopy (FTIR) and two dimensional correlation spectroscopy (2DIR) is used to observe and investigate the crystallization behaviour of iPB in scCO₂ and compressed CO₂. Based on the transform sequence given by 2DIR analysis, this transformation of helical chain structures is found to be initiated with the motion of side chains and followed by the movement of main chains. It is speculated that the motion of polymer chains was enhanced with the diffusion of CO₂. Also this crystalline transition is observed even in compressed CO₂, suggesting that CO₂ could also diffused into polymer under high pressure near the critical pressure. This diffusion of CO₂ is indicated by the growth of IR bands being assigned to the stretching vibration of C–O. A further investigation on the mechanically heating and freely cooling of iPB provides more evidences on the process of structure transition. The result implies that the nucleus of tetragonal form II formed in the melt is not affected by the existence of scCO₂, but the crystallization temperature become obviously lower.     

芳烃油对聚丁烯-1热塑性弹性体防水卷材性能的影响

考察了芳烃油用量对聚丁烯-1热塑性弹性体防水卷材物理力学性能及热氧老化和耐碱性能的影响.结果表明随着芳烃油用量的增加,材料的拉伸强度、撕裂强度、定伸应力等下降,断裂伸长率上升;经过80℃×168 h热氧老化后,材料的断裂伸长率保持率和拉伸强度保持率均随着芳烃油用量的增加呈减小的趋势,硬度普遍上升;经过质量分数为10%的NaO)H 168 h腐蚀后,材料的断裂伸长率保持率和拉伸强度保持率随着芳烃油用量的增加呈下降趋势,硬度普遍上升;芳烃油的最佳用量为25份.     

TiCl4／MgCl2-AIEt3体系合成聚1-丁烯

以负载钛体系（简称Ti）为主催化剂,三乙基铝（简称Al为助催化剂,加氢汽油为溶剂,用溶液聚合法合成了聚1-丁烯。研究了n（Ti）／n（Bt）、n（Al）／n（Ti）、反应温度、反应时间对转化率、催化效率、聚合物的特性粘数[η]及其全同立构含量的影响。结果表明,随n（Ti）／n（Bt）增加,转化率和催化效率都不断提高;随n（Al）／n（Ti）增加、反应温度升高,转化率和催化效率呈先上升后下降趋势;随n（Al）／n（Ti）、n（Ti）／n（Bt）增大和反应温度的升高,特性粘数逐渐下降,但其对全同立构含量影响较小。     

负载钛体系催化合成聚1-丁烯热塑性弹性体

研究了采用TiCl4/MgCl2 Al(i Bu)3负载钛催化体系合成聚1 丁烯(PBt)热塑性弹性体的规律。结果表明:最佳聚合条件是:Bt质量分数25%,n(Ti)∶n(Bt)=1×10-5∶1,n(Al)∶n(Ti)=(200～300)∶1,温度30℃。与聚合瓶小试条件相比,由于有良好的搅拌增加了传热传质效果,因此可获得更高的聚合速率和产率,且所合成的PBt的Mw和不溶物含量均较相同聚合条件下聚合瓶中的有所降低;氢气可有效调节PBt相对分子质量。