共查询到19条相似文献,搜索用时 171 毫秒
1.
2.
3.
采用动态DSC法研究了酚改性氰酸酯树脂体系的固化反应动力行为。研究表明:有机钛催化剂的加入降低了改性氰酸酯的固化反应的活化能和反应温度,加快了固化反应的速率;建立了酚改性氰酸酯树脂体系的固化反应动力学模型,反应级数都为1;有机钛催化剂的加入并不改变体系的固化反应机理。 相似文献
4.
5.
6.
氰酸酯改性环氧树脂的研究进展 总被引:3,自引:0,他引:3
氰酸酯改性环氧树脂是一种新型的具有广阔应用前景的高性能复合基体材料。综述氰酸酯改性环氧树脂的反应历程、反应条件对固化反应产物的影响及在工业领域中的应用。 相似文献
7.
8.
9.
一种双酚A型氰酸酯树脂流变特性及其改性研究 总被引:1,自引:1,他引:0
本文采用平板法研究了一种双酚A型氰酸酯树脂的流变特性,通过恒温预固化的方法对其进行改性,并借助红外光谱、差示扫描量热法(DSC)和凝胶渗透色谱法(GPC)等手段分析了预固化对氰酸酯树脂化学结构的影响.在此基础上,针对S-2玻璃纤维/氰酸酯复合材料层板,采用热压机工艺考察了加压时机和预固化对层板成型质量的影响.研究结果表明,该氰酸酯树脂反应活性低且流动性高,热压工艺中树脂流动不易控制;预固化可使氰酸酯树脂发生一定程度的自聚反应,从而降低其流动性,可明显改善氰酸酯树脂的工艺性,提高了层板的成型质量. 相似文献
10.
11.
We have developed the curing agents that have good storage stability for cyanate ester resins. It should be noted that these agents can be given rapid and efficient curing at low temperatures around 100°C. Even though the nucleophilicity was reduced by a phenol-amine salts consisting of basic aliphatic amines and weakly acidic phenols, the curing reaction with the cyanate ester occurred immediately. It means that the control of the curing reaction with cyanate esters is not easy due to the equilibrium between phenol and amine. In order to overcome this difficultly cyanate esters reactivity, the molecular motions suppression by polymer was applied in addition to the phenol-amine salts. The effect of the suppression for hardeners was studied in terms of the storage stability and reactivity to cyanate esters. It has been found out that PSM-EPEDA composed of ethylenediamine-epoxy adducts and novolac phenolic resin exhibits a large storage stability against cyanate esters by its effective suppression of molecular motions accompanied with efficient and rapid curing around 100°C. 相似文献
12.
Bong Sup Kim 《应用聚合物科学杂志》1997,65(1):85-90
Epoxy resin (diglycidyl ether of bisphenol A, DGEBA)/cyanate ester mixtures were cured with a curing agent, 4,4′-diaminodiphenylsulfone, and the effect of cyanate ester resin on the cure behavior and thermal stability in the epoxy resin was investigated with a Fourier transform infrared spectrometer, a rheometer, a dynamic mechanical analyzer, and a thermogravimetric analyzer. Cure reactions in the epoxy/cyanate ester mixture were faster than that of the neat epoxy system. The cure reaction was accelerated by increasing the cyanate ester resin component. Glass transition temperature and thermal stability in the cured resins were increased with increasing cyanate ester resin component. This may be caused by the increase of crosslinking density due to the polycyclotrimerization of the cyanate ester monomer to form triazine rings and the reaction of cyanate ester resin with the epoxy network. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 65: 85–90, 1997 相似文献
13.
14.
A novel cyanate ester, 2,6‐dimethyl phenol dipentene cyanate ester (DPCY), was successfully synthesized from cyanogen bromide with 2,6‐dimethyl phenol dipentene novolac, which was synthesized from dipentene and 2,6‐dimethyl phenol. For the purpose of increasing the mobility of residual DPCY during the final stage of curing and achieving a complete reaction of cyanate groups, a small quantity of a monofunctional cyanate ester, 4‐tert‐butyl phenol cyanate ester, was added to DPCY to form a cyanate ester copolymer. The thermal properties of the cured cyanate ester resins were studied by dynamic mechanical analysis, dielectric analysis, and thermogravimetric analysis. These data were compared with those of the commercial bisphenol A cyanate ester system. The cured modified cyanate ester exhibited a dielectric constant of 2.59–2.50, a dissipation factor of 0.0055–0.0089, and moisture absorption of 0.91–1.17%; these values were all lower than those of the as‐cured bisphenol A dicyanate system. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 369–379, 2005 相似文献
15.
16.
17.
在玻璃布增强氰酸酯树脂(CE)基复合材料中加入氮化硼(BN)粒子,制得CE/玻璃布/BN复合材料。研究了BN粒子含量对复合材料性能的影响。结果表明,经偶联剂处理的BN粒子使体系凝胶时间缩短,反应活性略有提高。BN粒子的加入可以明显提高复合材料的弯曲强度和层间剪切强度,在BN加入量为8 %时,复合材料的弯曲强度和层间剪切强度达到最大值,分别提高了5 %和36 %。加入BN粒子后,复合材料的起始热分解温度都较未填充体系有所提高,耐热指数升高,热稳定性相应提高。 相似文献
18.
采用硅烷偶联剂表面处理过的纳米二氧化硅作为无机填料改性氰酸酯树脂/聚苯醚固化体系,并利用非等温差示扫描量热法研究了氰酸酯树脂/聚苯醚/纳米二氧化硅电子封装材料的固化动力学。结果表明,氰酸酯树脂/聚苯醚/3%纳米二氧化硅固化体系的凝胶温度为150℃、固化温度为181℃、后处理温度为239℃;固化动力学参数表观活化能为15.46kJ/mol、反应级数为0.82、频率因子为38174.38s-1;加入纳米二氧化硅可以降低氰酸酯树脂/聚苯醚固化体系的表观活化能,使其固化反应可以在较低温度下进行。 相似文献
19.
端羟基聚丁二烯改性氰酸酯体系固化反应动力学 总被引:1,自引:0,他引:1
采用示差扫描量热法(DSC)研究了端羟基聚丁二烯(HTPB)改性双酚A型氰酸酯树脂(BADCy)体系的固化反应动力学,根据Arrhenius方程对固化过程动力学参数进行了求解,建立了固化反应动力学模型。结果表明,随着HTPB含量的增大,动态DSC固化反应放热峰向低温方向移动,说明HTPB可以催化固化反应并降低体系的反应温度。纯BADCy和BADCy/15%HTPB体系等温固化符合自催化反应模型。纯BADCy体系以及BADCy/15%HTPB体系的表观反应活化能分别为59.67 kJ/mol、56.91 kJ/mol。 相似文献