不同环境下杜仲胶/丁腈橡胶共混胶的性能

将杜仲胶(EUG)与丁腈橡胶(NBR)共混,研究了共混胶的硫化特性、结晶行为、力学性能以及不同环境下的老化性能。结果表明,当EUG用量为10份(质量,下同)时,EUG/NBR混炼胶的焦烧时间和正硫化时间以及硫化胶的拉伸强度和扯断伸长率均达到最大值。添加一定量的EUG对NBR硫化胶的耐盐雾和耐紫外线性能均能起到一定程度的改善作用,而共混硫化胶的硬度和耐油性能均在EUG用量为20份时体现最佳值。差示扫描量热分析表明,上述现象产生的原因在于共混硫化胶中存在的微晶及EUG与NBR的相容性所致。     

天然杜仲橡胶/聚丙烯热塑性硫化胶的性能与微观形貌

通过双螺杆挤出机制备了天然杜仲橡胶（EUG）/聚丙烯（PP）热塑性硫化胶（TPV）,考察了EUG用量对TPV物理机械性能、冲击强度、耐溶剂性能、耐热稳定性与结晶性能的影响,并表征了TPV的微观形貌。结果表明,随着EUG用量的增加,EUG/PP TPV的拉伸强度、扯断伸长率和邵尔D硬度逐渐下降,冲击强度逐渐增大,耐溶剂性能先提高后略有下降,耐热稳定性提高,结晶度先增大后减小,综合考虑,当EUG用量为60份时可制得综合性能较佳的TPV;随着EUG用量的增加,PP球晶完整性下降,存在无定形区,TPV接近均相体系。     

增容剂对硅橡胶/热塑性聚氨酯热塑性硫化胶性能的影响

采用动态硫化法制备了甲基乙烯基硅橡胶（MVQ）/热塑性聚氨酯（TPU）共混型热塑性硫化胶（TPV）,考察了增容剂的种类及用量对TPV力学性能及加工流变性能的影响。结果表明,随着增容剂用量的增加,TPV的力学性能呈先上升后下降的趋势。相比于乙烯丙烯酸共聚物和乙烯与乙酸乙烯嵌段共聚物,用聚烯烃弹性体接枝马来酸酐（POE-g-MAH）作为增容剂时TPV的力学性能更为优异。3种增容剂均能提高TPV中MVQ相与TPU相的相容性。当POE-g-MAH的用量为6份时,TPV中MVQ相与TPU相的玻璃化转变温度靠近程度最大,两相界面较为模糊,增容效果最佳。     

生物基聚乳酸/环氧化天然橡胶热塑性硫化胶的制备及性能

采用动态硫化法制备了聚乳酸(PLA)/环氧化天然橡胶(ENR)热塑性硫化胶(TPV),考察了加工工艺对PLA/ENR TPV力学性能的影响,PLA/ENR的质量比对TPV的力学性能、相态结构及热稳定性的影响。结果表明,当加工温度为150℃、加工时间为7 min、转速为70 r/min、过氧化二异丙苯的质量分数为3%时,PLA/ENR TPV的综合性能最佳。随着ENR用量的增加,TPV的拉伸强度及压缩永久变形减小,而扯断伸长率增大。相态结构发生了由"海-岛"结构向双连续结构、最终又变成"海-岛"结构的转变。动态硫化后,PLA的热稳定性下降,ENR含量越高,初始质量损失温度越低。     

剪切速率对乙烯-丙烯酸酯橡胶/聚偏氟乙烯热塑性硫化胶性能的影响

采用动态硫化法制备了乙烯-丙烯酸酯橡胶（AEM）/聚偏氟乙烯（PVDF）热塑性硫化胶（TPV）,考察了动态硫化过程中转子剪切速率对TPV微观相态结构及性能的影响。结果表明,动态硫化过程中转子的剪切速率越快,AEM和PVDF更易发生相转变,微观相态结构更加精细,形成具有“海-岛”结构的TPV。随转子的剪切速率加快,TPV的拉伸强度和扯断伸长率均先增大后减少。当剪切速率为75 r/min时,AEM/PVDF TPV具有较好的力学性能,拉伸强度达到14.84 MPa,扯断伸长率为246%,TPV具有更加优异的耐热油和热空气老化性能。     

聚乳酸/邻苯二甲酸二辛脂/丁腈橡胶热塑性硫化胶的形态演变

采用动态硫化法制备了聚乳酸(PLA)/邻苯二甲酸二辛脂(DOP)/丁腈橡胶(NBR)共混型热塑性硫化胶(TPV),通过场发射扫描电子显微镜研究了动态硫化过程中橡胶相的形态演变,采用能量分散X射线谱研究了动态硫化产物微观相态的结构,并考察了动态硫化时间对TPV力学性能的影响。结果表明,随着动态硫化反应的进行,NBR相在交联的同时增大了与树脂相之间的黏度差,并形成独特的双连续相结构。在动态硫化过程中,两相的尺寸均随动态硫化时间的延长而明显减小,并由此带来了TPV力学性能的改善。     

有机蒙脱土/丁基橡胶/聚丙烯热塑性硫化胶的制备与性能

采用动态硫化法制备了有机蒙脱土（OMMT）/丁基橡胶（IIR）/聚丙烯（PP）热塑性硫化胶（TPV）,考察了OMMT的用量和IIR/PP的质量比对TPV的物理机械性能、动态力学性能及热性能的影响。结果表明,当OMMT的用量为20份时,TPV的物理机械性能较佳,Payne效应最弱,OMMT均匀地分布在基体中,阻尼性能较好,有效阻尼温域较大。OMMT对PP的结晶行为有促进作用,OMMT加入量越多,复合体系的结晶温度越高。当IIR/PP的质量比为60/40时,Payne效应较弱,体系中IIR、PP及OMMT之间的相容性较好。     

杜仲胶聚烯烃热塑性硫化胶研制成功

<正>近年来,沈阳化工大学杜仲胶研究团队先后进行了杜仲胶/聚烯烃(EUG/PP,EUG/POE)制备热塑性弹性体的研究工作,并成功制得耐冲击性能获得显著改善的杜仲胶聚烯烃热塑性硫化胶(TPV)。研究结果表明,在动态硫化EUG/PP共混体系中,随着EUG含量的增加,共混物的冲击强度有较大幅度的提升,并且极大改善了聚烯烃弹性体(POE)永久变形大问题。当EUG/PP橡塑比为7:3时,     

IIR再生胶/PP热塑性硫化胶的制备与性能研究

采用动态硫化法制备ⅡR再生胶/聚丙烯热塑性硫化胶(RⅡR/PPTPV).并对其性能进行研究.结果表明,当RⅡR/PP共混比为60/40时,TPV的综合物理性能较好;RⅡR/PP TPV的耐溶剂性能和热稳定性能较好,加工性能优异;扫描电子显微镜分析表明,RⅡR/PP TPV中的橡胶粒子细小,分散均匀,两相相容性较好,界面强度提高.     

混炼型聚氨酯橡胶/聚十二内酰胺热塑性硫化胶动态硫化历程与性能

采用动态硫化方法制备了混炼型聚氨酯橡胶（MPU）/聚十二内酰胺（PA 12）热塑性硫化胶（TPV）,通过控制动态硫化时间探究了该TPV的动态硫化历程,同时研究了不同动态硫化阶段共混物的物理机械性能和动态力学性能。结果表明,随着动态硫化时间的延长,MPU/PA 12 TPV逐步完成相转变,在温度和剪切作用下,MPU相由连续相转变为分散相,而PA 12则由分散相转变为连续相;随着动态硫化时间的延长,MPU/PA 12共混物的储能模量升高,损耗模量降低,损耗因子减小。此外,随着动态硫化时间的延长,MPU/PA 12共混物的综合力学性能提高。     

Highly toughened polylactide by renewable Eucommia ulmoides gum

Polylactide (PLA) derived from natural sources has attracted increasing interest and has provided a promising alternative to traditional plastics derived from petroleum sources. With no loss of environmental friendly features, PLA was highly toughened by Eucommia ulmoides gum (EUG) derived from Eucommia ulmoides oliv. The dynamic mechanical analysis, scanning electron microscopy (SEM), and differential scanning calorimetry results show that the PLA–EUG blends were immiscible systems. SEM micrographs revealed that EUG particles were well dispersed in the PLA matrix with number‐average particle diameters of 2–4 μm. The mechanical properties indicated that the tensile strength decreased with increasing EUG contents, but the elongation at break and the impact strength were enhanced. The notched impact strength of the blends improved by 5.9‐fold compared to that of neat PLA. The PLA–EUG blends exhibited distinct shear‐thinning behavior; this indicated good processability, and the storage modulus and loss modulus of the PLA–EUG blends increased with EUG content. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46017.     

硫化体系对氯化丁基橡胶/尼龙12动态硫化胶性能的影响

研究了氧化锌、N,N’-间苯撑双马来酰亚胺(HVA-2)/氧化锌和1,3-双柠糠酰亚胺甲基苯(PK 900)/氧化锌3种硫化体系下氯化丁基橡胶(CIIR)/尼龙(PA)12混炼胶的硫化特性及CIIR/PA 12动态硫化胶(TPV)的物理机械性能和微观相结构,并考察了PK 900与氧化锌不同配比对CIIR/PA 12TPV物理机械性能、流变性能及微观相结构的影响。结果表明,PK 900/氧化锌的硫化速率介于氧化锌和HVA-2/氧化锌两者之间,由其制备的TPV橡胶相粒径为1～2μm,均匀分布在树脂相中,物理机械性能最优;固定PK 900用量为3份时,随着氧化锌用量的减少,CIIR/PA 12 TPV的拉伸强度、扯断伸长率和100%定伸应力均呈现先增大后减小的趋势;当PK 900/氧化锌(质量比)为3/5时,CIIR/PA 12TPV的物理机械性能最佳,且呈现低剪切速率高黏度、高剪切速率低黏度的特性。     

Influence of blocked polyisocyanate on thermomechanical, shape memory and biodegradable properties of poly(lactic acid)/poly(ethylene glycol) blends

A series of shape memory biodegradable blends from poly(lactic acid) (PLA) and poly(ethylene glycol) (PEG) were prepared by solution casting method. Ethyl cellosolve-blocked polyisocyanate (EC-bp) was synthesized and used as a cross-linker to obtain cross-linked PLA/PEG blends. The chemical structure of the prepared composite was confirmed by Fourier transform infrared spectra. Thermomechanical, thermal and shape memory properties of the blends were investigated and compared by dynamic mechanical analysis, thermogravimetric analysis and shape memory testing. The results showed that EC-bp cross-linked PLA/PEG blends had better thermal and thermomechanical properties than non-cross-linked blends and displayed good shape memory effects in both shape fixity rate and shape recovery rate. Moreover, the effect of EC-bp addition on the rate of biodegradable degradation in a phosphate buffer solution (pH 7.4) was studied at 37?°C. The prepared cross-linked PLA/PEG blends demonstrated better degradation resistance compared to the non-cross-linked blends.     

反式聚异戊二烯/纳米碳化硅形状记忆复合材料的制备与性能

以反式聚异戊二烯（TPI）为基质,研究了纳米碳化硅用量对碳化硅/TPI形状记忆复合材料硫化特性、物理机械性能、热性能及形状记忆性能的影响。结果表明,随着碳化硅用量的增加,复合材料的焦烧时间和正硫化时间都逐渐缩短;拉伸强度呈现先增大后减小的趋势,硬度逐渐增大;结晶度逐渐降低,从纯TPI的16.5%下降至碳化硅用量20份（质量,下同）时的13.9%;碳化硅用量为10份时复合材料的单向形状记忆性能最好,而其双向形状记忆行为在应力为250 kPa时的形状回复率达到了最大值79.1%。     

转子转速对乙烯-乙酸乙烯酯共聚物/三元共聚尼龙热塑性硫化胶性能的影响

使用密炼机,采用动态硫化工艺制备了乙烯-乙酸乙烯酯共聚物/三元共聚尼龙热塑性硫化胶（EVM/tPA TPV）和乙烯-乙酸乙烯酯-甲基丙烯酸缩水甘油酯共聚物/三元共聚尼龙热塑性硫化胶（EVM-GMA/tPA TPV）,研究了转子转速对两种热塑性弹性体体力学性能和耐热油等性能的影响。结果表明,在一定范围内提高转子转速,热塑性弹性体的力学性能呈上升趋势,当转子转速为80 r/min时,两种热塑性弹性体的综合力学性能最佳;当转子转速达到60 r/min以上时,两种热塑性弹性体的耐热油性能良好;随着转子转速的增加,两种热塑性弹性体的弹性得到改善;在相同转子转速条件下,EVM-GMA/tPA TPV比EVM/tPA TPV具有更好的力学性能、弹性和耐热油性能。     

Influence of Graphene Oxide on Thermally Induced Shape Memory Behavior of PLA/TPU Blends: Correlation with Morphology,Creep Behavior,Crystallinity, and Dynamic Mechanical Properties

In this study, shape memory is thermally induced in a series of graphene oxide (GO) filled poly(lactic acid)/thermoplastic polyurethane (PLA/TPU) blends, prepared via melt mixing process, and their shape recovery and shape fixity are measured, and the results are correlated with morphology, dynamic mechanical properties, crystallinity and creep recovery behavior. Morphological analysis by scanning and transmission electron microscopy reveals that the blends are immiscible, and GO platelets are mainly localized in the TPU phase of the blends, which lead to smaller and more elongated TPU droplets with improved interfacial adhesion being responsible for the improved shape recovery performance compared to the unfilled blend. A systematic enhancement found in storage and Young's modulus, tensile strength, creep resistance and creep recovery, and cold crystallinity as a result of GO inclusion are in agreement with the improved shape recovery, shape fixity and overall shape memory performance of the filled systems. The developed PLA/TPU/GO nanocomposites with highly improved mechanical properties can be utilized as a new class of environmentally friendly shape memory materials for a broad range of applications.     

Preparation and thermo-electric properties of graphene/thermoplastic vulcanizate composites

石墨烯/热塑性硫化胶复合材料的制备及热电性能 汤 琦,崔勇胤,颜桐桐,曹 兰,宗成中（青岛科技大学 高分子科学与工程学院,山东 青岛 266042） 通过熔融共混方式制备了石墨烯（Ge）/聚丙烯母粒,然后采用动态硫化的方法与丁基橡胶共混制备Ge/热塑性硫化胶（TPV）复合材料,研究了Ge/TPV复合材料的相态结构、热电性能和力学性能。结果表明,丁基橡胶交联颗粒以微米级长条状分散在聚丙烯母粒基质中,Ge表面褶皱明显,片层厚度较薄,均匀分散在聚丙烯母粒相和橡塑两相界面中。丁基橡胶交联颗粒能够排斥Ge,从而提高Ge/TPV复合材料的热电性能。与纯TPV相比,Ge/TPV复合材料（Ge质量分数2%）的交流电导率增加了1个数量级,介电常数增加了1.6倍,热导率增加了44.2%。Ge/TPV复合材料的热电性能及力学性能因Ge的存在而大幅提高。