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1.
主要研究了丁腈橡胶(NBR)/聚氯乙烯(PVC)/酚醛树脂(PR)/受阻酚AO60共混体系中PR、AO60和增塑剂癸二酸二丁酯(DS)的用量对硫化橡胶力学性能和阻尼性能的影响。在共混体系中添加不超过50phr的AO60,其硫化胶损耗因子-温度曲线仍呈现单峰特征,体系相容性良好。随着AO60含量的增加,硫化胶的玻璃化转变温度提高,阻尼峰值增大。拉伸强度及动态模量先随之增高,然后降低。随着PR含量的增加,硫化胶的拉伸强度随之增加,tanδ峰值温度升高,而阻尼峰值则先提高后降低。加入增塑剂,硫化胶的力学性能、储能模量及玻璃化转变温度都有不同程度的降低。  相似文献   

2.
超高分子量聚乙烯/聚丙烯共混体系流变行为及形态的研究汪晓东,励杭泉,金日光(北京化工大学高分子系,北京,100029)关键词共混合金,线性互穿网络,双连续相,网络增韧机理通常聚合物的增韧机理是在树脂中引人柔性链段[1]形成复合物(如橡塑共混物),这些...  相似文献   

3.
苯乙烯-乙烯共聚物的合成及其结构性能的研究   总被引:1,自引:0,他引:1  
用负载型钛系催化剂MgCl_2/TiCl_4,NdCl_3/AlEt_3(SN-1催化剂)制备出组份比例变化的苯乙烯-乙烯共聚产物.共聚产物通过溶剂萃取分离、~13C-NMR、IR、动态粘弹谱进行表征,并初步进行了与聚苯乙烯(aPS)共混作用的研究.结果表明,SN-1催化剂能有效地催化苯乙烯与乙烯共聚合.共聚产物为含有均聚聚苯乙烯的共聚物复合物,其中的25mol%的苯乙烯参加了共聚.共聚产物与aPS共混可明显提高aPS的冲击强度和断裂伸长率.  相似文献   

4.
苯乙烯-乙烯共聚物的合成及其结构性能的研究   总被引:1,自引:0,他引:1  
用负载型钛系催化剂MgCl2/TiCl4,NdCl3/AlEt3(SN-1催化剂)制备出组份比例变化的苯乙烯-乙烯共聚产物,共聚产物通过溶剂萃取分离,^13C-NMR,IR,动态粘弹谱进行表征,并初步进行了与聚苯乙烯共混作用的研究。结果表明,SN-1催化剂能有效地催化苯乙烯与乙烯共聚合,共聚产物为含有均聚聚苯乙烯的共聚复合物,其中约25mol%的苯乙烯参加了共聚。共聚产物与aPS共混可明显提高aP  相似文献   

5.
碳笼烯(C_(60)/C_(70))载体钕系催化异戊二烯聚合   总被引:2,自引:0,他引:2  
较系统地研究了Nd(naph)3 C60X Al(i Bu)3碳笼烯钕系催化异戊二烯配位聚合的反应规律,并测定了聚合物分子量、分子量分布和微观结构.碳笼烯钕系为一均相体系.Al/Nd及Cl/Nd摩尔比对催化体系的活性、聚合物分子量都有较大的影响,活性中心的形成有很好的时间和温度的稳定性.PIp的特性粘数[η]在2左右,分子量分布MW/Mn在3左右,均小于传统钕催化体系.PIp的顺式含量大于97%.  相似文献   

6.
用傅立叶红外光谱(FTIR)中差示光谱技术研究了具有特殊相行为的羧化聚苯醚(CPPO)和聚苯乙烯(PS)共混体系特征红外吸收谱带随相区的转变而发生的变化.发现当核化度为8.0mol%时,CPPO/PS共混体系的红外特征吸收峰的频率位移速率随温度的变化与该体系的特殊相行为(即同时具有UCST和LCST)有相互对应关系.研究了随温度变化,共混体系中分子间特殊相互作用的变化.探讨了此共混体系相容和相分离的机理.  相似文献   

7.
PS/LDPE共混体系相结构的TEM研究徐世爱,江明,沈静姝(复旦大学高分子科学系和聚合物分子工程实验室,上海,200433)(中国科学院化学研究所高分子物理开放实验室)关键词相结构,透射电镜,共混体系聚苯乙烯(PS)和低密度聚乙烯(LDPE)共混体...  相似文献   

8.
用DSC方法研究了羧化聚苯醚(CPPO)/磺化聚苯乙烯(SPS)、以及它们对应的碱金属离子(Li+、Na+、Cs+)中和的离聚物共混体系的相容性.结果表明,这一体系具有较宽的相容范围,金属离子的引入使共混体系的相容性有所变化,Li+和Cs+能促进相容性,而Na+则使相溶性略有减弱.  相似文献   

9.
SIS-PAn导电橡胶复合物的制备和性能   总被引:5,自引:0,他引:5  
用原位聚合方法在SIS(苯乙烯-异戊二烯-苯乙烯嵌段共聚物)橡胶基体中合成聚苯胺(PAn),可形成均匀复合的SIS-PAn导电橡胶膜.成膜后紧朝玻璃的膜面导电,而朝向空气的膜面却绝缘.膜中PAn的含量只有5.8%(质量分数)或An/SIS的投料比为0.2时,导电复合物膜的表面电阻和导电率即可分别达到300Ω/□和0.07S·cm~(-1)分析了制备条件,包括PAn含量、酸量、氧化剂用量、表面活性剂用量、交联剂用量和模具材料等因素对SIS-PAn复合物导电性能的影响.  相似文献   

10.
研究了磺化聚苯乙烯离聚体/聚(苯乙烯-4-乙烯吡啶)共混体系,磺化聚苯醚离聚体/聚(苯乙烯-4-乙烯吡啶)共混体系的磺化聚苯醚离聚体/胺化聚苯醚共混体系在氯仿/甲醇混合溶剂中的粘度行为,结果表明,和它们分别对应的不含离子基的共混物相比,这三个共混体系都表现出较高的比较粘度,这是由于体系中的酸基及其盐和含氮碱基的引入,在共混组分间产生了强烈的离子相互作用,从而导致分子间的缔合,使比浓粘度提高,并讨论  相似文献   

11.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

12.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

13.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

14.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

15.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

16.
Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.  相似文献   

17.
用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.  相似文献   

18.
19.
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).  相似文献   

20.
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.  相似文献   

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