PVC/环氧树脂E51共混物性能的研究

以504及554/504分别作为固化剂,采用锥形双螺杆挤出机实现了PVC与环氧树脂的熔融共混,制备了PVC/环氧树脂E51共混物。固化剂用量为环氧树脂E51用量的80%时,研究了环氧树脂E51用量、固化剂组成及固化时间对PVC/环氧树脂E51共混物力学性能及维卡软化温度的影响。结果表明:以504及554/504为固化剂,少量环氧树脂E51(4份以内)加入PVC后,有助于提高共混物的拉伸强度、弯曲强度;当环氧树脂E51为2份、固化时间为8h时,共混物维卡软化温度达到最大值100.2℃,比纯PVC高出16.5℃。     

PVC/环氧树脂F51共混物性能的研究(二)

以554/504为固化剂,研究了不同固化时间下,F51用量对PVC/F51共混物的微观形貌、力学性能和维卡软化温度的影响。结果表明:①少量的F51在PVC基体中分散比较均匀,F51用量较多时会出现团聚现象;②少量的F51有利于提高PVC/F51共混物的力学性能和维卡软化温度,用量以2～6份为宜;③随着固化时间的延长,PVC/F51共混物的力学性能和维卡软化温度均提高;④固化剂554可进一步提高PVC/F51共混物的拉伸强度和弯曲强度,但会降低缺口冲击强度和维卡软化温度。     

用差示扫描量热法研究环氧树脂的固化特性

利用差示扫描量热法研究了芳纶复合材料的环氧树脂基体（改性环氧树脂F－46）中固化剂合量对树脂基体固化反应温度，反应热的影响，结果表明，当固化剂含量低于20质量份时，树脂基体的固化反应热随固化剂含量的增加而增加，当固化剂含量超过20质量份后，固化反应热开始下降，此环氧树脂基体的最低固化反应温度为114.3℃，固化反应峰值温度为169.3℃，固化反应表观活化能为80.35kJ/mol,固化反应级数为0.91.     

软质PVC环/氧树脂共混物性能的研究

考察了PVC/环氧树脂(E51)共混物(未固化与固化)的力学性能和加工性能,采用电子扫描显微镜观察了粒子在基体中的分散情况。结果表明:①在试验条件下,E51质量分数为5%(以PVC/E51质量为100%计,下同)时,试样的力学性能较好。②当E51质量分数为10%时,共混物的最大转矩最低;当E51质量分数为13%时,共混物的平衡转矩最低。③经过固化的试样的力学性能优于未固化的试样。④E51的加入能够改善试样的相容性与粒子的分散效果。     

环氧树脂/丙烯酸锌潜伏性固化体系制备及性能

以潜伏型固化剂丙烯酸锌(ZDA)和双酚A型环氧树脂（E-51）为主要原料,经过物理共混的方法制备了环氧树脂混合物,并用红外光谱对混合物固化前后的结构进行表征。采用非等温差示扫描量热法研究了ZDA的含量对环氧树脂/ZDA耐高温固化体系的固化行为和性能的影响,通过Kissinger和Ozawa法来计算固化反应的表观活化能（Ea）。结果表明,随着ZDA含量的增加,固化反应的活化能降低,反应更容易进行;随着ZDA含量的增加,环氧树脂固化物的热稳定性随之降低;当ZDA的含量为15份时,弯曲强度、弯曲模量和拉伸强度都达到最大值,分别为88.82 MPa、2.64 GPa和46.70 MPa;逐步增加固化剂的含量,固化物会出现脆性的转变,材料的韧性得到了提高。     

高性能双组分环氧树脂建筑结构胶的研制

以E-51环氧树脂为主体,自制改性聚酰胺380T与二乙烯三胺共混作为固化剂,研究了380T与二乙烯三胺的配比、固化剂用量、填料种类及用量,确定了最佳配方及固化条件。当mE51/m380T/m二乙烯三胺/m石英砂=100/26/4/(200～300)时,结构胶常温固化7d的拉伸强度和剪切强度可分别达到52MPa和19.2MPa,是一种力学性能优、粘接力强、韧性好、触变性及湿润性优的高性能双组分环氧树脂建筑结构胶。     

高性能UV延迟固化结构胶的制备及其性能研究

采用双酚A环氧树脂为主体树脂、少量聚氨酯预聚体和端羧基丁腈橡胶为增韧剂,紫外延迟固化剂（T1647）为引发剂,添加少量硅烷偶联剂（KH560）制备高性能UV延迟固化结构胶,研究紫外延迟固化胶用量、光源功率、紫外光照时间对UV延迟胶施胶影响,以及温固化时间、温度和高温固化时间对延迟固化剂性能的影响,结果表明：延迟固化剂用量为1.2%、紫外光功率为800 W、照射时间为9 s时,延迟固化剂凝胶时间为8～9 min。常温固化时间为1 h、剪切强度为3.47 MPa、120℃烘烤24 h后,剪切强度能达25 MPa;180℃烘烤3 h,最高达33.78 MPa。     

间苯二酚二缩水甘油醚的制备及其应用

采用三苯基磷作醚化催化剂,粉状氢氧化钠作闭环剂合成了间苯二酚二缩水甘油醚(RDGE),其环氧值为0.80,在25℃时粘度为0.36 Pa.s,示差扫描量热仪(DSC)检测表明,其固化放热峰比双酚A型环氧树脂(E51)降低了约15℃。RDGE对E51有非常显著的稀释作用,二者共混,大大提高了通用环氧树脂的综合性能。采用593#固化剂时,RDGE和E51的拉伸强度分别为75.17 MPa和58.58 MPa,前者比后者高出28%,RDGE与E51共混固化物的拉伸强度随RDGE含量的增加而呈线性增加;593#固化的RDGE/E51共混体系,弯曲强度和弯曲模量均随RDGE用量的增加而呈线性增加,弯曲强度由E51的112.77 MPa增加到RDGE的123.75 MPa,弯曲模量由E51的1.79 GPa增加到RDGE的2.40 GPa。     

有机硅改性环氧树脂

东华大学的虞鑫海等人以含活性氨基的硅树脂（SR22000）、环氧树脂（ECC202）为原料，K—12为固化剂、2E4M1为固化促进剂，通过配方设计，得到有机硅改性环氧树脂粘接剂。有机硅改性环氧树脂的凝胶化时间随着温度的增加而减少，其室温拉伸剪切强度受硅树脂用量的影响较大，当硅树脂用量为8份以下时，其拉伸剪切强度保持在20MPa以上；     

改性己二胺柔性固化剂的合成与性能研究

采用二官能度环氧树脂对己二胺进行改性,得到了一种含多段长亚甲基链段的柔性固化剂。利用红外光谱表征其基本结构,通过60℃下的在线红外检测以及不同温度下固化时间对力学强度影响的分析,初步确定了其最佳固化工艺条件为80℃×6h。通过热重分析法（TG）测试了不同固化剂用量的固化产物热稳定性,并采用差示扫描量热法（DSC）研究了该固化剂固化时放热状况,进一步得到并验证了前面工作的正确性。以环氧树脂E-44为主体树脂,分别对其固化物在-196℃、室温、60℃下的剪切强度、90°剥离强度进行探讨。当主体树脂与固化剂按1∶0.5质量比混合时,其在各温度下的拉伸剪切强度分别为16.84MPa、14.73MPa和13.52MPa,可满足实际应用的要求。     

Effect of epoxy resin on morphology and physical properties of PVC/organophilic montmorillonite nanocomposites

Poly(vinyl chloride)/organophilic montmorillonite (PVC/OMMT) nanocomposites were prepared by means of melt blending. A liquid epoxy resin was used to aid PVC chains in intercalating into silicate layers. The effects of the preparation methods and epoxy resin contents on the melt intercalation of PVC were investigated. The morphology development, mechanical properties and optical properties of the PVC/OMMT composites were tested as functions of epoxy resin content and OMMT content. Wide‐angle X‐ray diffraction, transmission electron microscopy and scanning electron microscopy were used to characterize the morphology of the resulting composites. After being pretreated by the epoxy resin, the OMMT layers were largely intercalated into the PVC matrix, and even exfoliated at high epoxy resin content. The addition of epoxy resin led to a decrease in optical clarity of the composites but improved the processing stability, as indicated by yellowness index and haze measurement. However, the optical clarity of the composites containing 4 phr of epoxy resin (PVC/E‐OMMT) was improved by increasing the OMMT content, as shown by light transmission. Both the tensile strength and notched Izod impact strength of the PVC/E‐OMMT composites reached their maximum values when the OMMT content was 0.5 phr and the epoxy resin content was 2 phr. With further increase of the OMMT content and the epoxy resin content, the tensile strength decreased but was still higher than that of original PVC. The method of addition of epoxy resin had little effect on the physical properties but mainly influenced the morphology of PVC/OMMT nanocomposites. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2184–2191, 2003     

双组分高强度环氧胶粘剂的研制

根据车间内钢梁上吊车轨道安装底板与钢梁粘接的具体要求,研制了一种中温固化双组分环氧胶粘剂。探讨了E-51、E-39D和纳米碳酸钙用量对甲组分粘度的影响,测试了不同促进剂的胶粘剂凝胶时间并研究了粘接表面处理、中温固化时间对胶粘剂剪切强度的影响。结果表明,通过选用不同粘度的环氧树脂并添加纳米碳酸钙,控制甲组分粘度在8～20Pa.s,选用促进剂M3份,表面制备并采用偶联剂处理后,100℃下固化2h后,该胶铝-铝、钢-钢剪切强度可达45MPa和51MPa,实现了胶粘体系中温高强度快速固化。室温放置20h后钢-钢剪切强度为5.8MPa,可以安装加热设备以便后固化。     

一种回转体类构件用中低温固化环氧树脂体系研究

采用等温黏度实验和浇铸体力学性能测试来优选自制改性固化剂CUR–1的配比,通过不同升温速率下的固化过程差示扫描量热并对固化物进行傅立叶变换红外光谱分析,确定了体系的固化制度,研制出一种适用于发动机壳体或结构复杂的回转体类结构件的碳纤维湿法缠绕树脂基复合材料的中低温固化环氧树脂体系,用湿法缠绕工艺制作单向纤维缠绕成型复合材料环(NOL环)并进行了性能测试。结果表明:当CUR–1的含量为15份时,树脂体系具有适于湿法缠绕工艺的黏度和使用期,树脂可在80℃完全固化,同时浇铸体拉伸强度为84 MPa,拉伸弹性模量为3.8 GPa,断裂伸长率为5.4%,热变形温度为131℃。该树脂体系与纤维粘结性好,NOL环力学性能高,NOL环拉伸强度为2 451 MPa,拉伸弹性模量为146 GPa,层剪切强度为55 MPa。     

聚丙烯/马来酸酐接枝聚丙烯/环氧树脂/玻璃纤维复合材料的制备及其性能研究

通过双螺杆挤出机制备了聚丙烯/马来酸酐接枝聚丙烯/环氧树脂/玻璃纤维（PP/PP-g-MAH/EP/GF）复合材料,并研究了PP-g-MAH含量、EP含量及固化剂对复合材料力学性能的影响。结果表明,PP-g-MAH含量为10份,含有固化剂EP的含量为3份时,复合材料的综合力学性能最佳;与不加EP的复合材料相比,其拉伸强度、弯曲强度、冲击强度分别提高了41 %、47 %、86 %。扫描电子显微镜分析表明,EP的加入明显改善了GF和PP基体的黏结强度。     

Effect of epoxy resin on thermal,dynamic, and mechanical properties of rigid poly(vinyl chloride)

This work is concerned with the effect of an epoxy resin on the properties of rigid poly(vinyl chloride) (PVC). The epoxy resin concentrations of 0, 1, 2, 4, and 6 phr were used to prepare PVC/epoxy polymer blends and the viscoelastic behavior of the blends was investigated by dynamic mechanical thermal analysis and rheometry test. The results revealed that the low molecular weight epoxy resin did not greatly affect the viscoelastic properties of PVC. From the morphological point of view, the smallest droplet size of epoxy dispersed in the polymer blends was found in the sample with 1 phr epoxy resin, and the largest one was for the sample with 6 phr epoxy. The thermal properties of PVC/epoxy blends were investigated using differential scanning calorimetry and thermogravimetric analysis, as well. According to our research, the initial decomposition temperature of PVC was increased about 6°C by the incorporation of epoxy resin. The results of tensile test showed that the addition of epoxy resin decreased the elongation‐at‐break of PVC about 50% in the samples without calcium carbonate and about 25% in the samples containing calcium carbonate. Moreover, the failure mode of PVC was changed from a ductile fracture mode to a brittle fracture mode with the addition of epoxy resin. J. VINYL ADDIT. TECHNOL., 25:E72–E79, 2019. © 2018 Society of Plastics Engineers     

RTM工艺用双酚F型环氧树脂体系研究

本文选用二乙烯三胺和二乙氨基丙胺作固化剂,系统地研究了用于RTM工艺的低粘度双酚F型环氧常温固化体系的工艺特性及力学性能。研究结果表明,用二乙烯三胺固化双酚F型环氧时,其固化物力学性能优异,但适用期较短;用二乙氨基丙胺部分替代二乙烯三胺,得到了适用期为36m in的树脂体系(二乙烯三胺用量2phr、二乙氨基丙胺用量4phr),其树脂固化物拉伸强度为66.8MPa,弯曲强度为102.0MPa。用所确定的树脂体系制得的碳纤维复合材料综合力学性能优良,树脂与碳纤维界面粘结良好,将其应用于RTM成型某型号舱段的制备,制品综合性能优良。     

Super-Toughened Fumed-Silica-Reinforced Thiol-Epoxy Composites Containing Epoxide-Terminated Polydimethylsiloxanes

In response to the demand for high-performance materials, epoxy thermosetting and its composites are widely used in various industries. However, their poor toughness, resulting from the high crosslinking density of the epoxy network, must be improved to expand their application to the manufacturing of flexible products. In this study, ductile epoxy thermosetting was produced using thiol compounds with functionalities of 2 and 3 as curing agents. The mechanical properties of the epoxy were further enhanced by incorporating fumed silica into it. To increase the filler dispersion, epoxide-terminated polydimethylsiloxane was synthesized and used as a composite component. Thanks to the polysiloxane–silica interaction, the nanosilica was uniformly dispersed in the epoxy composites, and their mechanical properties improved with increasing fumed silica content up to 5 phr (parts per hundred parts of epoxy resin). The toughness and impact strength of the composite containing 5 phr nanosilica were 5.17 (±0.13) MJ/m³ and 69.8 (±1.3) KJ/m², respectively.     

公路路面超薄石脂面层胶黏剂拉伸性能及影响机理

超薄石脂面层具有轻薄、抗滑、施工效率高等特性,在路面铺装中已得到广泛应用.通过配合比试验制备了用于公路路面超薄石脂面层铺装的胶黏剂,通过树脂浇铸体拉伸试验研究了不同种类、不同用量的增韧剂、稀释剂和固化剂对胶黏剂拉伸性能的影响,并通过SEM和FTIR试验,探讨了各添加剂对拉伸性能的影响机理.结果表明:超薄石脂面层胶黏剂中A组分(环氧树脂及改性剂)最佳配比为:环氧树脂E-51:环氧树脂E-44:增韧剂F1:稀释剂D1:阻燃剂=50:50:20:10:8,B组分(固化剂及改性剂)最佳配比为:固化剂H1:促进剂:偶联剂=70:10:2;随增韧剂或稀释剂含量的增加,试件抗拉强度先升高后降低,弹性模量持续降低,断裂伸长率则不断升高;胶黏剂固化物抗拉强度为21.83 MPa,拉伸弹性模量为0.47 GPa,断裂伸长率为38.24％;增韧剂中聚氨酯与环氧树脂相互缠绕、贯穿成网络结构,出现互穿包容效应,起到增韧作用,稀释剂通过降低胶黏剂的交联密度来增进延展性,固化剂中氨基与环氧基发生固化反应.