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。     

离子液改性白炭黑对天然橡胶性能的影响

采用一定用量的离子液氯化1-烯丙基-3-甲基咪唑（AMI）对白炭黑进行表面改性,用差示扫描量热仪对改性白炭黑进行了表征,考察了改性白炭黑对天然橡胶（NR）复合材料硫化特性、力学性能和动态力学性能的影响。结果表明,AMI和白炭黑之间存在较强的相互作用;当白炭黑用量少于30份时,随着改性白炭黑用量的增加,混炼胶的正硫化时间缩短,硫化速率提高;当白炭黑用量为30份时,NR复合材料的力学性能最佳,增强作用最明显,与不加改性白炭黑的试样相比拉伸强度增加了30.8%,撕裂强度提高了188.9%,磨耗体积减小了76.0%;与白炭黑填充的NR硫化胶相比,改性白炭黑填充的NR硫化胶的玻璃化转变温度升高,储能模量增大,改性白炭黑与NR之间的相互作用较白炭黑更强。     

高导热天然橡胶基厚制品的制备及性能

考察了氧化铝、碳纳米管(CNT)及二者并用对天然橡胶基厚制品加工性能、物理机械性能和导热性能的影响。结果表明,CNT与氧化铝并用可显著提高天然橡胶的100%和300%定伸应力、撕裂强度及邵尔A硬度,降低压缩永久变形。在天然橡胶中加入质量分数为30%的氧化铝和质量分数为2%的CNT,其导热系数可达0.241 W/(m·K),较天然橡胶提高了35.39%。     

An eco-friendly approach for toughening of polylactic acid from itaconic acid based elastomer

Sustainable and biocompatible novel lactic acid based bioelastomer (LBPE) was synthesized by polycondensation process which has been confirmed by FTIR and ¹H NMR. Owing to the resemblances in the lactate structures of polylactic acid (PLA) and LBPE, the synthesized LBPE bioelastomers can act as an excellent PLA toughener in presence of free radical initiator dicumyl peroxide (DCP). The mechanical, morphological and thermal were investigated. Chemical crosslinks endow the LBPE with relatively high elasticity and environmental stability which ultimately enhances the mechanical properties of PLA matrix.     

Design of room temperature high self-healing efficiency natural rubber based on ionic supramolecular network

The introduction of ion association is one of the most effective ap-proaches to achieve the self-healing behavior of rubber. However, most commercially availabl...     

各向同性与各向异性天然橡胶磁流变弹性体的导热性能及磁流变性能（英文）

采用羰基铁粉粒子填充天然橡胶磁流变弹性体(MRE),研究了各向同性与各向异性MRE的磁流变性能及导热性能。结果表明,各向异性MRE的热扩散系数和导热系数比各向同性MRE分别提高了30. 1%和41. 9%。同时,随着应变的增大,MRE的相对磁流变效应呈下降趋势,而在相同应变下,各向异性MRE的储能模量以及相对磁流变效应均高于各向同性MRE。     

胶粉中二氧化硅的原位生成及其在天然橡胶中的应用

通过溶胶-凝胶法在胶粉中原位生成纳米二氧化硅网络,经傅里叶变换红外光谱和热重分析,结果证实在溶胶-凝胶反应中于胶粉表面过渡层中可原位生成质量分数约3%～5%的类似二氧化硅的网络结构.改性胶粉表现出更好的热稳定性,失重5%的温度比未改性时提高了约30%.将50份(质量)改性胶粉填充到天然橡胶中后,所得天然橡胶/改性胶粉复合材料仍具有较好的物理机械性能和动态力学性能.     

基于离子超分子网络实现自修复天然橡胶的制备

将甲基丙烯酸锌（ZDMA）或聚（甲基丙烯酸锌）低聚物（PM）引入到天然橡胶中,同时并用炭黑/白炭黑与天然橡胶共混,制备一种具有自修复性能的耐屈挠疲劳橡胶。研究结果表明,与PM相比,ZDMA可形成以离子交联为主的可逆超分子网络,赋予了硫化胶更好的自修复功能,当其用量为40份（质量）时硫化胶的自修复效率最高,接近100%。不饱和羧酸盐（ZDMA或PM）与传统填料（炭黑和白炭黑）并用时,PM仅在前期可有效抑制裂纹的扩展,ZDMA可明显提高材料的耐屈挠疲劳性能,当m（ZDMA）/m（炭黑）为20/40时硫化胶的耐屈挠疲劳性能最好。     

Effect of zinc stearate on the rheology of ionic elastomer based on carboxylated nitrile rubber

Monsanto rheometry, melt viscometry, differential scanning calorimetry, and dynamic mechanical spectroscopy have been used to study the effects of zinc stearate on the rheological behavior of ionomer based on carboxylated nitrile rubber (XNBR) - zinc oxide (ZnO) system. At temperatures below its melting point, zinc stearate functions as a reinforcing agent for ionomer formation. Above its melting point, it acts as a plasticizer for the ionic domains, thereby facilitating easy processing of the ionomer.     

NR/SBR并用橡胶基磁敏橡胶的制备及性能的研究

通过湿法预处理,用偶联剂KH-570对羰基铁粉进行表面改性,制备了综合性能较好的并用橡胶基实用型磁敏橡胶,研究了羰基铁粉含量对天然橡胶/丁苯橡胶(NR/SBR)并用橡胶基磁敏橡胶性能的影响;同时利用扫描电镜研究了改性羰基铁粉表面和磁敏橡胶复合材料断面的微观结构。结果表明,通过偶联剂改性的羰基铁粉其晶体结构未发生变化,且表面有一层致密的包覆层;以NR/SBR并用橡胶为基体的磁敏橡胶,当羰基铁粉用量为300份时,可表现出较好的机械性能和磁流变效应。     

用高锰酸钾氧化法制备液体天然橡胶

以天然橡胶干胶片为原料,在较低的温度条件下采用高锰酸钾作氧化剂,通过氧化降解法制备了低相对分子质量的液体天然橡胶,考察了高锰酸钾的用量、反应温度、反应时间及高锰酸钾水溶液的pH值对液体天然橡胶相对分子质量和结构的影响。结果表明,高锰酸钾水溶液的pH值为4时,在35℃下反应4 h,氧化1 g天然橡胶干胶时高锰酸钾的最佳用量为0.005 mol,所制备液体天然橡胶的黏均分子量为3 970,收率达到77%。红外光谱分析表明液体天然橡胶的端基是以羰基和羧基为主。     

基于废旧轮胎胶粉的热塑性弹性体的制备及发泡性能研究

通过沥青改性胶粉及采用相容剂与聚丙烯共混制备了性能优良的热塑性弹性体(TPE)材料,并以超临界流体为发泡剂对其发泡性能进行了研究。实验结果表明,胶粉通过沥青改性后,可以明显地提高TPE的拉断伸长率,并且发泡TPE的泡孔平均直径增大,泡孔密度减少,相对密度减小,但是随着沥青用量的增加,材料的粘度降低,从而出现泡孔破裂和塌陷现象,最后导致泡孔平均直径和泡孔密度减小,相对密度增加。相容剂苯乙烯嵌段共聚物接枝马来酸酐(SEBS-g-MA)可以提TPE的拉断伸长率并改善泡孔结构。温度的升高和饱和压力的增大,都导致了发泡弹性体的泡孔增大,泡孔密度和相对密度减小。     

Preparation of dynamically vulcanized thermoplastic elastomer nanocomposites based on LLDPE/reclaimed rubber

Dynamically vulcanized thermoplastic elastomers nanocomposites (TPV nanocomposites) based on linear low density polyethylene (LLDPE)/reclaimed rubber/organoclay were prepared via one‐step melt blending process. Maleic anhydride grafted polyethylene (PE‐g‐MA) was used as a compatibilizing agent. The effects of reclaimed rubber content (10, 30, and 50 wt %), nanoclay content (3, 5, and 7 wt %), and PE‐g‐MA on the microstructure, thermal behavior, mechanical properties, and rheological behavior of the nanocomposites were studied. The TPV nanocomposites were characterized by X‐ray diffraction, transmission electron microscopy, scanning electron microscopy (SEM), differential scanning calorimeter, mechanical properties, and rheometry in small amplitude oscillatory shear. SEM photomicrographs of the etched samples showed that the elastomer particles were dispersed homogeneously throughout the polyethylene matrix and the size of rubber particles was reduced with introduction of the organoclay particles and compatibilizer. The effects of different nanoclay contents, different rubber contents, and compatibilizer on mechanical properties were investigated. Increasing the amount of nanoclay content and adding the compatibilizer result in an improvement of the tensile modulus of the TPV nanocomposite samples. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

离子液体在合成橡胶中的应用研究进展

综述了离子液体在合成橡胶的加氢反应、硫化和填料改性等方面的应用,着重总结了其在碳纳米颗粒和无机纳米颗粒填料改性中的应用。     

废旧轮胎胶粉对热塑性聚氨酯弹性体性能的影响

将废旧轮胎胶粉（WRP）与聚四氢呋喃二醇型热塑性聚氨酯（PU）共混制备了一系列不同WRP含量的PU/WRP共混材料,通过傅里叶变换红外光谱和扫描电子显微镜研究了WRP在PU基体中的分散性以及二者间的结合作用,考察了WRP含量对共混材料性能的影响。结果表明,在PU/WRP共混材料中,WRP削弱了PU硬硬段之间的氢键作用,增强了硬软段间的氢键结合程度,且WRP均匀分散在PU基体中,与PU基体有一定程度的相容性,但与PU基体的附着力较弱;与纯PU相比较,PU/WRP共混材料的邵尔A硬度变化不大,300%定伸应力增大,拉伸强度减小,且随着WRP含量的增加,300%定伸应力和拉伸强度先小幅增大后减小,当WRP质量分数达到20%时,300%定伸应力和拉伸强度达到最大值;PU/WRP共混材料的耐磨性能、耐水性能和耐油性能均低于纯PU,其中WRP质量分数为20%时,共混材料的耐水性能和耐油性能相对较好。     

不同无卤阻燃体系硫化天然橡胶的制备及性能

将6种新型无卤阻燃体系分别与天然橡胶共混制得无卤阻燃天然橡胶（FRNR）,并对其阻燃性能、抗疲劳性能及热失重行为进行了研究。结果表明,6种无卤阻燃剂体系使得FRNR阻燃性能得到不同程度的提高,其中以二乙基次磷酸铝（Al Pi）和三聚氰胺氰尿酸盐（MCA）复配阻燃剂及可膨胀石墨（EG）阻燃剂的阻燃效果最为突出,可使FRNR的热释放速率降低近50%。六苯氧基环三磷腈、10-（2,5-二羟基苯基）-10-氢-9-氧杂-10-磷杂菲-10-氧化物和EG的加入对FRNR的抗疲劳性能影响较小,因而基于该3种阻燃体系的FRNR的抗疲劳性能与纯天然橡胶相当。Al Pi/MCA及EG的优良阻燃效果与其成炭能力呈正相关。     

Preparation and characterization of organoclay nanocomposites based on natural rubber

Rubber compounds based on natural rubber (NR) reinforced with octadecylamine‐modified bentonite have been prepared via a vulcanization process and characterized by several techniques. The silicate nanolayers are exfoliated and uniformly dispersed in the polymer chains. Monsanto measurements have shown that the organoclay accelerates the vulcanization reaction and, furthermore, gives rise to a marked increase of the torque, indicating that the elastomer becomes more crosslinked in the presence of the organoclay. These results were corrobated by swelling measurements since a noticeable increase in the curing degree was observed when the organoclay was added to the rubber recipe. Moreover, thermodynamic parameters have shown an increase in the structural order of the nanocomposite. In addition, thermal analysis supports the assumption that the degree of curing of the elastomer increases when the organoclay is added to the elastomer. An appreciable increase of the involved heat during the curing reaction has been observed. Moreover, the T_g of the NR increases in the presence of the organoclay due to the confinement of the elastomer segment into the organoclay nanolayers, which restricts the mobility of the chains. Copyright © 2003 Society of Chemical Industry     

用原位改性黑色页岩粉填充天然橡胶及其性能

采用X射线衍射、红外光谱等手段表征了黑色页岩粉,利用在天然橡胶中预先混入的硬脂酸于混炼过程中原位改性的方法制备了黑色页岩粉与炭黑复合填充的天然橡胶,研究了黑色页岩粉用量对天然橡胶硫化特性、力学性能和耐老化性能的影响,并用扫描电镜观察了复合材料断面的微观形貌。结果表明,用10份(质量,下同)硬脂酸原位改性的黑色页岩粉替代炭黑,与20份炭黑并用填充的天然橡胶表现出优于完全由炭黑填充者的拉伸性能和耐老化性能。在同等用量情况下(40份),填充有原位改性黑色页岩粉天然橡胶的硫化特性和力学性能均优于用传统方法改性黑色页岩粉填充的天然橡胶。     

Facial fabrication of self-healing natural rubber foam based on zinc thiolate ionic networks

In this work, self-healing natural rubber (SHNR) foam incorporating an intrinsic zinc thiolate ionic network was successfully prepared. The materials exhibited the ability to autonomously repair damage at room temperature without the need for external triggers. The investigation focused on the effect of sodium bicarbonate, employed as a blowing agent, on the self-healing performance, as well as the physical and mechanical properties of the foam. Various concentrations of sodium bicarbonate (0, 1, 4, 8, and 10 phr) were employed. The conventional two-roller mill was used for mixing and compounding, while compression molding was utilized for the vulcanization process. With increasing sodium bicarbonate concentration, the density, tensile strength, elongation at break, and compression set of the self-healing NR foam were found to decreased. Conversely, the porosity, shrinkage, compressive strength, and water uptake of the SHNR foam increased as the concentration of sodium bicarbonate increased. Scanning electron microscopy analysis revealed that the optimal concentration of sodium bicarbonate (8 phr) resulted in smaller, finer, and more uniform porous structures. The self-healing rubber foam incorporating 8 phr sodium bicarbonate exhibited improved properties in terms of tensile modulus, elongation at break, and tear strength, with healing efficiencies of 91.27%, 69.39%, and 83.99%, respectively.     

新型天然橡胶吸油材料的制备及性能

以天然橡胶(NR)接枝马来酸酐(NR-g-MAH)和NR接枝甲基丙烯酸甲酯(NR-g-MMA)为NR/甲基丙烯酸十八酯-丙烯酸丁酯-苯乙烯共聚物(SMA-BA-St)吸油材料的增容剂,研究了各组分配比、增容剂的种类及用量对吸油材料吸油能力和力学性能的影响,并采用热重分析及扫描电子显微镜对吸油材料进行了表征。结果表明,以NR-g-MAH为增容剂时,吸油材料的力学性能和吸油率优于以NR-g-MMA为增容剂时的吸油材料;当NR/SMA-BA-St/NR-g-MAH(质量比)为100/10/5时,材料具有较好的力学性能、吸油性能和老化性能;随着增容剂接枝率的增大,吸油材料的力学性能和吸油性能呈上升趋势;吸油材料在CCl4、甲苯、苯、柴油和机油中的饱和吸油率分别为37.48,32.45,29.26,23.06,16.79g/g,保油率可超过85%;对CCl4的二次吸油率可达30g/g;以NR-g-MAH和NR-g-MMA增容吸油材料的热稳定性比SMA-BA-St优异,且在常温下使用很稳定;NR-g-MAH的增容效果优于NR-g-MMA,有效改善了NR与SMA-BA-St的相容性。