查询词典 styrenes

Seven 7-styrylcoumarins were synthesized by palladium-catalyzed Heck reaction of coumarin diazonium salts with substituted styrenes.

采用钯催化香豆素重氮盐的Heck反应合成了七个7-位苯乙烯基取代香豆素化合物，该方法反应条件温和且收率较高。

In the three systems, system realizes the crosslinking of PVC bases on the peroxide crosslinking mechanism, the tensile strength of crosslinked PVC has been improved somewhat, the IR spectrum of gel demonstrates that there are characteristic absorption peaks of n-alcohol that belongs to ethanol amine and benzenoid group. From the analysis of gel structure , deduces that the mechanism of crosslinking reaction: under the initiations of peroxide and high temperature, PVC yields macromolecules free radicals, at the same time , styrene"s polymerization and grafting onto PVC takes place, at last the system forms crosslinking structure through coupling between radicals; confirms that triethanol amine can absorb HC1 produced by degradation of PVC, so improves the crosslinking efficiency of peroxide, decreases the HCl"s promotion for PVC"s degradation; deduces that triethanol amine can activate the PVC macromolecules and prolong the free radicals" life-time of PVC macromolecules; the effect to the PVC macromolecule makes styrenes graft reaction easy, and thus improves the crosslinking efficiency.

三种体系中三乙醇胺/过氧化二异丙苯/苯乙烯体系基于过氧化物交联机理实现了聚氯乙烯的交联，聚氯乙烯交联后拉伸强度有一定提高，凝胶红外光谱分析证实了凝胶结构中含有乙醇胺的伯醇基团特征吸收和苯环的特征吸收，由凝胶结构分析，推断出交联反应的机理：聚氯乙烯在过氧化物和热作用下产生大分子自由基，苯乙烯在过氧化物和大分子自由基的作用下发生聚合和接枝反应，最终通过自由基之间的偶合产生交联；证实三乙醇胺可以吸收聚氯乙烯分解产生的HCl，提高了过氧化物的交联效率，消弱了HCl对聚氯乙烯降解的促进作用；推断三乙醇胺可以活化聚氯乙烯大分子并有可能使聚氯乙烯大分子自由基存在的时间得以延长，对聚氯乙烯大分子的作用使苯乙烯的接枝反应易于发生，从而提高了交联效率。

Sythesis and application of chlorostyrene-DVB strongly acidic cation exchange resin ;2. For this study,a series of poly( p -amino styrenes) with various amounts of supported hydrogen chloride,and a series of strongly acidic cation exchange resin s with various exchange capacity were synthesized,and their catalytic property for ketalization of cyclohexanone and glycol were investigated.

通过测定固载了不同量的氯化氢的聚和不同交换量的强酸性阳离子交换树脂催化的环己酮与乙二醇的缩酮化反应缩酮的收率，研究了聚合物固体酸催化剂的疏水性对其催化缩酮化反应性能的影响；发现在一定范围内增加催化剂的疏水性，可提高缩酮化反应的收率。

Based on the pure styrenes polymerization, the inhibited polymerization by inhibitor was studied. The effect of polymerization temperature, the addition of ethylbenzene, the content of inhibitor, and the compound of inhibitors was measured for the bulk thermal polymerization of styrene.

在纯苯乙烯聚合基础上，着重考察了阻聚剂(缓聚剂DNBP和阻聚剂M)阻聚下苯乙烯的聚合行为，并系统研究了聚合温度、乙苯含量、缓聚剂及阻聚剂含量、阻聚剂的复配对苯乙烯本体热聚合动力学的影响规律。

A series of new isoxazolines were prepared by 1,3-dipolar cycloaddition between different mono-substituted styrenes and new 1,3-dipolar compounds which were synthesized by the reaction of N-methylhydroxylamine sulfate with aromatic carbonyl compounds.

以N-甲羟胺硫酸盐和芳香族羰基化合物为主要原料合成了一系列不同的1，3-偶极化合物，并合成了四种不同的单取代苯乙烯。以该系列1，3-偶极化合物和单取代苯乙烯为主要中间体，采用1，3-偶极环加成反应合成了一系列异恶唑啉类新化合物。

The shape memory effect of poly{2,5-bis[(4-butoxyphenyl)oxycarbonyl]-styrenes} fiber was studied by TA-Q800 Dynamic Mechanical Analysis. According to the research results, the outstanding shape recovery ability of PBPCS fiber was found. The recovery rate was fastest above 145℃. It cost about 9 minutes recovering from 400% strain to origin length. The repeatability of shape memory was good in 5 repeated times.

本文采用TA-Q800动态热机械分析仪研究了聚乙烯基对苯二甲酸二酯纤维的形变回复性能，发现PBPCS纤维具有非常好的形状记忆效应，在145℃及以上温度，形状回复速率最好，9min左右可以从400％的伸长回复到原来的尺寸，于145℃，重复实验5次，结果说明形变回复重复性好。

The ee's of30-93% and yields of 64-96% were achieved in NaClO / 4-PPNO and m-CPBA /NMO oxidant systems by using substituted styrenes and substituted2,2-dimethylchromenes as substrates.

在优化反应条件下，在NaClO／4-PPNO、m-CPBA／NMO两个氧化体系中，对取代苯乙烯系列底物获得了30～70％ee和64～96％的收率；对取代苯并吡喃类化合物，获得了84～93％ee和82～96％的收率。

But we don't care about Battlegrounds.

但我们并不在乎沙场中的显露。

Ah! don't mention it, the butcher's shop is a horror.

啊！不用提了。提到肉，真是糟透了。