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Differential Polymorphic Transformation Behavior of Polybutene-1 with Multiple Isotactic Sequences

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Chinese Journal of Polymer Science 2020年第2期38卷 164-173,I0007页

作者： Ya-Ping Ma Wei-Ping Zheng Chen-Guang Liu hua-Feng Shao hua-Rong Nie ai-hua he Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-Plastics (Ministry of Education) Qingdao University of Science and Technology

For the solid-solid transformation from form Ⅱ to form Ⅰ of isotactic polybutene-1(iPB),the temperature dependence of form Ⅰ nucleation and growth was deemed to control the transformation ***,the relationship between formⅠ formation and form Ⅱ disappearance in the transformation process is not *** this work,the spontaneous crystal transformation from form Ⅱ to Ⅰ of iPB with 81 mol%mmmm sequence concentration is studied firstly by tracking the two processes,the decay of form Ⅱ and the yielding of form Ⅰ in a wide range of temperature spanning from 0℃ to 50℃ and in a long transformation time ranging from 5 min to 65 days with in situ FTIR and *** the literature reports,the decay rate of form Ⅱ is firstly found to be lower than the yielding rate of form Ⅰ at all studied temperatures,especially at low transition *** is attributed to the amorphous chains which locate near crystal lamella participating into the nucleation of form Ⅱ.The regular chain folding and growth of i PB form Ⅰ from amorphous chains containing short isotactic sequences also lead to an increase in crystallinity of form Ⅰ compared with that of initial form Ⅱ crystallized at 60℃.An increase in the annealing temperature results in decrease in crystallinity and increase in lamellae thickness of i PB formⅠ.

关键词： Polybutene-1 Polymorphic transformation Isotactic sequence Crystallinity Lamellae thickness

The Influence of Trans-1,4-poly(butadiene-co-isoprene) Copolymer Rubbers(TBIR) with Different Molecular Weights on the NR/TBIR Blends

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Chinese Journal of Polymer Science 2019年第10期37卷 966-973,I0003页

作者： Hao Wang Ri-Guo Wang Yun-Sheng Ma Bo Luan ai-hua he Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-plastics(Ministry of Education)School of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao 266042China Shandong huaju Polymer Material Co. Ltd.Binzhou 256500China

The molecular weight of a polymer is of prime importance and greatly influences the processing and mechanical properties of the polymer. Trans-1,4-poly(butadiene-co-isoprene) multi-block copolymer rubbers(TBIR) exhibit outstanding fatigue resistance, low heat build-up and good abrasion resistance, and are expected to be desirable candidate for high performance tire. Study on the influence of TBIR with different molecular weights on the structure and properties of TBIR and natural rubber(NR)/TBIR blends is essential to understand its contribution to the greatly improved dynamic properties of the rubber vulcanizates. TBIR with different molecular weights characterized by 1H-NMR, 13C-NMR, GPC, and DSC were highly trans-1,4-copolymers with similar chain sequence distribution and crystalline trans-1,4-polyisoprene(TPI) blocks. The green strength and modulus of TBIR increased with the increasing molecular *** NR/TBIR compounds filled with 40 phr carbon black were chemically cured by sulfur for the preparation of NR/TBIR *** compatibility between NR and TBIR, filler distribution, crosslinking bond and density, and properties of NR/TBIR vulcanizates were studied. The NR/TBIR vulcanizates showed increasing tensile strength, hardness, modulus, rebound, abrasion resistance, and flexural fatigue properties with increasing molecular weight of TBIR. Furthermore, they presented significant improvement in flexural fatigue resistance when compared with that of NR vulcanizate. The contribution mechanism of TBIR on the NR/TBIR blends was discussed. The TBIR with a wide range of molecular weight are ideal rubbers for high performance tires.

关键词： Trans-1,4-poly(butadiene-co-isoprene)copolymer rubber Nature rubber Blends Molecular weight Fatigue resistance

Structure and Properties of Isotactic Polypropylene/Polybutene-1 In-reactor Alloys

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Chinese Journal of Polymer Science 2020年第12期38卷 1382-1391页

作者： Ya-Ping Ma Ning Zhang Wei-Ping Zheng ai-hua he Chen-Guang Liu Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber Plastis(Ministry of Education)School of Polymer Science and EngineeringQingdao University ofScience and Technology Qingdao 266042China

The composition and structure of polymer largely determine the properties of its final *** a novel polymer material,the composition,structure,and properties of the isotactic polypropylene/polybutene-1 in-reactor alloy(PPIPB alloy)synthesized by sequential two-stage polymerization with Ziegler-Natta catalyst were correlated for the first time in this *** iPP/PB alloy was fractionated by temperature rising elution fractionation(TREF)in a broad temperature ranged from-30℃ to 140℃,and the chain microstructures and sequence distributions of isolated fractions were analyzed by DSC,GPC,13C-NMR,and *** iPP/IPB alloy was composed of five components,namely high isotactic PB(PB,85.8 wt96),medium isotactic PB(mPB,5.1 wt%),polyl(butene-1)-block propylene copolymers(PB-6 PP,4.1 wt%6)which contained PB and PP blocks with dfferent lengths according to the isolation temperature,isotactic PP(iPP,2.7 wt%6),and atactic PB(aPB,2.3 wt96).Compared to other commercial pipe materials,the P/iPB alloy presented outstanding thermal creep resistance and gas permeability resistance,high strength and low deformation at high temperature,and appropriate flexural *** roles of PP and PB-b-PP components in the alloy were *** work is expected to elucidate the potential application of PPIPB aloy as pipe materials and provide solutions for the design and synthesis of high performance pipe materials.

关键词： Polybutene-1 Aloy Block copolymer Structure Property

Polymerization Kinetics of Propylene with the MgCl_(2)-Supported Ziegler-Natta Catalysts——Active Centers with Different Tacticity and Fragmentation of the Catalyst

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Chinese Journal of Polymer Science 2021年第1期39卷 70-80,I0006页

作者： Wei-Ping Zheng Ya-Ping Ma Da-Lin Du ai-hua he hua-Feng Shao Chen-Guang Liu Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-Plastics(Ministry of Education)School of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao 266042China

The catalytic activity and stereospecificity of olefin polymerization by using heterogeneous TiCl_(4)/MgCl_(2) Ziegler-Natta(Z-N) catalysts are determined by the structure and nature of active centers, which are mysterious and fairly controversial. In this work, the propylene polymerization kinetics under different polymerization temperatures by using Z-N catalysts were investigated through monitoring the concentration of active centers [C*] with different tacticity. SEM was applied to characterize the catalyst morphologies and growing polypropylene(PP) particles. The lamellar thickness and crystallizability of PP obtained under different polymerization conditions were analyzed by DSC and SAXS. The PP fractions and active centers with different tacticity were obtained with solvent extraction fractionation method. The catalytic activity, active centers with different tacticity and propagation rate constant kp, fragmentation of the catalyst, crystalline structure of PP are correlated with temperature and time for propylene polymerizations. The polymerization temperature and time show complex influences on the propylene polymerization. The higher polymerization temperature(60 ℃) resulted higher activity, kp and lower [C*], and the isotactic active centers Ci* as the majority ones producing the highest isotactic polypropylene(iPP) components showed much higher kp when compared with the active centers with lower stereoselectivity. Appropriate polymerization time provided full fragmentation of the catalyst and minimum diffusion limitation. This work aims to elucidate the formation and evolution of active centers with different tacticity under different polymerization temperature and time and its relations with the fragmentation of the PP/catalyst particles, and provide the solutions to the improvement of catalyst activity and isotacticity of PP.

关键词： Polypropylene Catalytic activity Active center Catalyst fragmentation

The Effect of In situ Melt Pre-shear Induced Oriented Precursors on the Crystallization of Poly(1-butene)/Polypropylene Blends

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Chinese Journal of Polymer Science 2024年第12期42卷 2011-2020,I0012页

作者： Wen-Kang Wei Jing-Jing Zhao Chen-Guang Liu Dong Wang ai-hua he Shandong Provincial Key Laboratory of Olefin Catalysis and Polymerization Key Laboratory of Rubber-Plastics(Ministry of Education)School of Polymer Science and EngineeringQingdao University of Science and TechnologyQingdao266042China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing100029China

Melt pre-shear induced crystallization of polymer blends holds great significance in industrial processing and product *** this work,two typical PB/PP blends(50/50,90/10),possessing commercial value and academic hotspot,were employed to investigate the effect of melt pre-shear on the crystallization of isotactic poly(1-butene)(PB)and polypropylene(PP)by applying shearing slightly above the melting temperature of PP with subsequent non-isothermal crystallization to simulate actual processing *** was discovered that in PB/PP(90/10)blend,in situ melt pre-shear generated oriented PP precursors induced the formation of PP-FIC(Flow-induced crystallization)which acted as row crystal nucleus significantly promoting PB crystallization into spherulite with higher melting temperatures(T_(m)),crystallinity(X_(c)),and thicker lamellar thickness(d_(c)).While in PB/PP(50/50)blend,the melt pre-shear generated PP-shish precursors induced the formation of PP shish-kebab that exerted a confining effect on the crystal growth of PB,resulting in truncated spherulite formation with higher T_(m) and thicker d_(c) but lower X_(c).This research provides insight into the mechanism underlying oriented crystal structure formation,crystal properties,and phase morphology of PB/PP blends under melt pre-shear fields,which have significant theoretical and practical implications for their industrial processing and preparation of high-performance products.

关键词： Meltpre-shear PB/PPblends Precursors Crystallization

高反式-1,4-丁二烯-异戊二烯共聚橡胶的结构表征及其在轿车轮胎子口护胶中的应用研究

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高分子学报 2015年第12期25卷 1387-1395页

作者：王浩邹陈贺爱华山东省烯烃催化与聚合重点实验室橡塑材料与工程教育部重点实验室青岛科技大学高分子科学与工程学院青岛266042

采用逐步等温结晶分级法对高反式-1,4-丁二烯-异戊二烯共聚橡胶(TBIR)进行分级并对各级份进行了结构与组成表征.结果表明,TBIR-20为丁二烯单元无规分布、异戊二烯嵌段形成结晶的共聚物,TBIR-40为含TPB嵌段、TPI嵌段的共聚物;TBIR应用于... 详细信息

采用逐步等温结晶分级法对高反式-1,4-丁二烯-异戊二烯共聚橡胶(TBIR)进行分级并对各级份进行了结构与组成表征.结果表明,TBIR-20为丁二烯单元无规分布、异戊二烯嵌段形成结晶的共聚物,TBIR-40为含TPB嵌段、TPI嵌段的共聚物;TBIR应用于轮胎子口护胶,可使混炼胶结晶度、格林强度和硬度增大,硫化速度加快;含TBIR的共混硫化胶的其他性能保持不变,压缩温升显著降低,耐磨耗性能和耐老化性能明显提高;DMA结果表明NR与TBIR的相容性优于BR,TEM结果表明并用TBIR后硫化胶中炭黑分散性更好.在轿车子午线轮胎子口护胶中应用20份左右的TBIR,其他力学性能保持在较高水平的同时,耐磨性、耐曲挠和耐老化性能显著提高,压缩温升明显降低.

关键词：反式-1,4-,丁二烯异戊二烯共聚物轮胎子口护胶

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聚丁烯及聚丁烯合金的溶液等温结晶行为研究

高分子学报 2018年第6期28卷 765-772页

作者：邹义刘晨光贺爱华山东省烯烃催化与聚合重点实验室橡塑材料与工程教育部重点实验室青岛科技大学高分子科学与工程学院青岛266042

研究了聚丁烯-1(PB-1)及聚丁烯合金(PBA)中PB-1的溶液等温结晶行为.测定了PB-1在正庚烷溶剂中的溶解度曲线,采用膨胀计法研究了PB-1和PBA中PB-1组分的溶液等温结晶动力学.研究发现,等温结晶温度的升高会降低PB-1的结晶速率,但不影响PB-... 详细信息

研究了聚丁烯-1(PB-1)及聚丁烯合金(PBA)中PB-1的溶液等温结晶行为.测定了PB-1在正庚烷溶剂中的溶解度曲线,采用膨胀计法研究了PB-1和PBA中PB-1组分的溶液等温结晶动力学.研究发现,等温结晶温度的升高会降低PB-1的结晶速率,但不影响PB-1在溶液中的结晶成核方式;PBA中PB-1组分的溶液等温结晶速率更快,聚丙烯(PP)组分的存在改变了PB-1的结晶成核方式.示差扫描量热仪(DSC)和广角X射线衍射仪(WAXD)测试表明PB-1的溶液等温结晶形成I′和III晶型,结晶温度的提高与PP组分的存在都会促进PB-1晶型III的产生.

关键词：聚丁烯聚丁烯合金溶解度溶液结晶等温结晶动力学

等规聚丁烯-1与等规聚丙烯间界面的结构与性能研究

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高分子学报 2023年第12期54卷 1891-1898页

作者：侯紫薇牛秀岳倩倩温帅刘永家贺爱华聂华荣青岛科技大学高分子科学与工程学院、山东省烯烃催化与聚合重点实验室、橡塑材料与工程教育部重点实验室青岛266042

基于构建的iPB-1与iPP的双层热压复合膜,设计两相界面结构,并通过撕裂实验、扫描电子显微镜(SEM)和透射电子显微镜(TEM),研究高温退火温度与结晶温度对iPB-1与iPP间界面结构和性能的影响.结果表明,iPB-1/iPP复合样品经退火处理后,界面... 详细信息

基于构建的iPB-1与iPP的双层热压复合膜,设计两相界面结构,并通过撕裂实验、扫描电子显微镜(SEM)和透射电子显微镜(TEM),研究高温退火温度与结晶温度对iPB-1与iPP间界面结构和性能的影响.结果表明,iPB-1/iPP复合样品经退火处理后,界面黏结强度明显下降,且退火温度越高,界面黏结强度和撕裂面粗糙度均越低.另外,经高温退火及两步降温结晶(即iPP于130℃先结晶、iPB-1于60℃后结晶)后,样品的平均界面黏结强度、撕裂面粗糙度、界面层厚度均比经一步降温结晶(iPP和iPB-1于60℃同时结晶)后的更高,且出现iPB-1分子链向iPP相区扩散的界面相结构.

关键词：等规聚丁烯-1 等规聚丙烯共混改性界面相结构

反式-1,4-丁二烯-异戊二烯共聚橡胶改性的高性能轿车轮胎胎面胶的结构与性能

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高分子学报 2018年第3期28卷 419-428页

作者：王浩宋丽媛马韵升王日国贺爱华山东省烯烃催化与聚合重点实验室橡塑材料与工程教育部重点实验室青岛科技大学高分子科学与工程学院青岛266042 山东省烯烃催化与聚合重点实验室黄河三角洲京博化工研究院有限公司滨州256500 山东华聚高分子材料有限公司滨州256500

研究了新一代合成橡胶-反式-1,4-丁二烯-异戊二烯共聚橡胶(TBIR)在高性能轿车轮胎胎面胶(溶聚丁苯橡胶/顺丁橡胶(SSBR/BR))中的应用及SSBR/BR/TBIR共混胶的结构与性能.结果表明,相对于无定型的SSBR和BR,TBIR由于具有一定的结晶性而呈现... 详细信息

研究了新一代合成橡胶-反式-1,4-丁二烯-异戊二烯共聚橡胶(TBIR)在高性能轿车轮胎胎面胶(溶聚丁苯橡胶/顺丁橡胶(SSBR/BR))中的应用及SSBR/BR/TBIR共混胶的结构与性能.结果表明,相对于无定型的SSBR和BR,TBIR由于具有一定的结晶性而呈现出较高的生胶强度、模量和韧性.但相比反式聚异戊二烯(TPI),由于丁二烯单体单元的引入降低了聚合物链的结构规整性,TBIR的结晶熔融焓、熔点和玻璃化转变温度均明显降低.采用10~20份TBIR与SSBR/BR并用改性,同时加入30份炭黑和45份白炭黑,SSBR/BR/TBIR混炼胶的格林强度和定伸应力提高,焦烧时间(tc10)和工艺正硫化时间(tc90)基本保持不变.SSBR/BR/TBIR混炼胶经过150oC硫化反应,制备的硫化胶物理机械性能优异,抗拉伸疲劳性能提高4.6~6.3倍,压缩强度提高21.4%~23.1%,耐磨耗性能提高10.8%~15.1%,耐湿滑性能提高13.6%~40.4%,滚动阻力维持不变.填料分散仪和透射电镜(TEM)结果表明,相比SSBR/BR硫化胶,SSBR/BR/TBIR硫化胶填料分散度提高7.3%~14.9%,填料聚集体平均尺寸降低1.4~2.7μm.可结晶的TBIR的高生胶强度及模量可显著抑制混炼胶中填料的聚集,改善硫化胶中填料的分散性,最终贡献于SSBR/BR/TBIR硫化胶优异的抗拉伸疲劳性、高的耐磨性、抗湿滑性、压缩强度、定伸模量等性能,TBIR是应用于高性能轿车轮胎胎面胶的一种理想新合成橡胶.

关键词：反式丁戊橡胶高性能轮胎胎面胶抗湿滑性能耐磨耗性能轮胎魔鬼三角