共查询到19条相似文献,搜索用时 125 毫秒
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聚醚改性硅油的合成研究 总被引:1,自引:0,他引:1
以六水合氯铂酸为催化剂,烯丙基聚醚(F-6)与含氢硅油为原料,在无溶剂甲苯的条件下,加热反应生成聚醚改性硅油,通过测定硅氢键的残余量来计算反应的转化率。分别研究了催化剂量、温度、烯丙基聚醚(F-6)与含氢硅油的物质的量比对反应转化率的影响,得出了最优化的反应条件为:催化剂的质量分数为1.5×10-5,温度120℃,n(聚醚)∶n(硅油)=1.20∶1.00。实验表明,合成的聚醚改性硅油可以有效降低溶剂型聚氨酯树脂溶液(As)树脂的表面张力,使其由30.4mN/m降到27.0mN/m。 相似文献
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以10-十一烯酸四氟丙酯(UATE)、聚醚(F-6)和苯基含氢硅油为原料,氯铂酸为催化剂,经硅氢加成反应合成了长链含氟烷基酯与聚醚共改性苯基含氢硅油(UAPFPS)。通过FT-IR和1H NMR对UAPFPS的结构进行了表征,采用单因素试验对反应中各影响因素进行考察得到其较佳工艺参数为:反应温度110 ℃,反应时间5.5 h,n(Si-H) ∶n(C=C)=1∶1.2,n(F-6) ∶ n(UATE)=1∶1,催化剂用量20 μg/g(相对于每克反应物)。在此条件下Si-H键转化率为95.30%。将UAPFPS、硅膏、乳化剂和增稠剂复配制得改性有机硅消泡剂,其性能测试结果表明,该消泡剂具有较好的消泡性、抑泡性与稳定性。 相似文献
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以不同相对分子质量的烯丙基聚氧乙烯醚和不同含氢量的含氢硅油为原料,在氯铂酸催化下进行硅氢加成反应制备了系列聚醚改性有机硅表面活性剂。通过对浑浊产物静置分层后的上、下层以及澄清产物分别进行核磁共振波谱分析,证明了将产物是否均一透明作为判定较佳反应条件的依据是可靠的。采用全面实验方案,综合考察了反应温度、反应时间和催化剂用量的影响,以产物性状是否无色透明为指标得出较佳反应条件:在烯丙基聚氧乙烯醚和含氢硅油的摩尔比n(C=C)∶n(Si-H)=1.2∶1的前提下,反应温度为100℃,反应时间为6 h,催化剂用量为1.03×10-4mol.L-1(以铂原子计)。考察了硅油含氢量和聚醚相对分子质量对产物性状的影响,结果表明,硅氢化过程中低含氢量的硅油和低相对分子质量的聚醚易得到均相透明的产物。 相似文献
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《有机硅材料》2015,(1)
以异丙醇为溶剂、氯铂酸为催化剂,将单烯丙基封端聚氧乙烯聚氧丙烯醚(AEP)、单烯丙基封端聚氧乙烯聚氧丙烯环氧基醚(AEPH)和单烯丙基封端聚氧乙烯氧聚丙烯乙酰基醚(AEPC)同时与含氢硅油进行硅氢加成反应,合成了羟基封端聚醚、环氧基封端聚醚和乙酰基封端聚醚共改性硅油破乳剂。通过IR和1H NMR对产物结构进行表征,证实得到了预期产物。通过单因素实验法考察了碳碳双键与硅氢键的量之比[n(CC)∶n(Si—H)]、反应时间、反应温度和催化剂用量对活性氢转化率的影响,确定的最佳反应条件为:n(CC)∶n(Si—H)=1.20∶1,反应时间6 h,反应温度100℃,催化剂用量40μg/g(相对于反应物总质量),在此条件下活性氢转化率达到93.72%。将该聚醚改性硅油进行原油破乳性能测试,结果显示,在聚醚改性硅油用量为100 mg/L、破乳温度70℃条件下,加入聚醚改性硅油2 h后,原油脱水率达到90.54%,具有较好的破乳性能。 相似文献
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以含氢硅油和丙烯酸十八酯为原料、氯铂酸为催化剂,通过硅氢加成反应合成了丙烯酸十八酯改性硅油。研究了催化剂用量、反应温度、反应时间和物料比等因素对反应的影响。通过正交实验和对相关因素的研究确定出反应的最佳条件:温度75℃,n(CC)∶n(Si—H)=1.1∶1,铂用量为反应物质量的0.008%,反应时间4 h,溶剂用量是反应物质量的30%;由红外表征证实,产物接枝上了丙烯酸十八酯。 相似文献
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以含氢硅油和烯丙基聚醚为原料,在氯铂酸螯合物的催化作用下,通过无溶剂硅氢加成反应合成了聚醚改性硅油。通过正交实验测定反应的转化率,探讨了反应时间、反应温度、催化剂用量以及反应物比例对反应的影响,并得出较适宜的反应条件为:反应时间为8h,反应温度为130℃,催化剂用量为20μg/g,反应物配比[n(Si-H)∶n(C=C)]为1∶1.2。在该条件下,含氢硅油中Si-H的转化率达94.45%。由此制备的流平剂能有效降低表面张力,且具有优良的流平性能。讨论了含氢硅油与烯丙基聚醚的结构差异对产品的表面性能的影响。 相似文献
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γ-(2,3-环氧丙氧)丙基硅氧烷耐高温树脂的合成及热性能 总被引:1,自引:0,他引:1
以γ-(2,3-环氧丙氧)丙基三甲氧基硅烷(GPTS)、酸催化剂和混合溶剂等为原料,采用水解-缩合法合成了含环氧基的硅氧烷杂化树脂。以黏度和环氧值为衡量指标,采用单因素试验法优选出制备该杂化树脂的较佳工艺条件,并对其热性能进行了表征。结果表明:在酸性介质中,当n(GPTS)∶n(水)∶n(酸催化剂)∶n(溶剂)=1∶3.0∶0.5∶7.7时,GPTS经水解、缩合反应后,可以获得黏度为1 270~1 320 mPa.s、环氧值为0.183的硅氧烷杂化树脂;该杂化树脂的起始分解温度为270.1℃,800℃时的残炭率(43.0%)相对较高,说明其热稳定性较好。 相似文献
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硅聚合物石刻涂料的合成 总被引:8,自引:0,他引:8
用有机硅烷RSiX3和SiX4经水解缩聚制备硅聚合物石质文物保护涂料。讨论了单体比例、水量、溶剂、催化剂、反应温度和时间对涂料性能的影响,列出了优化工艺条件下制备的涂料性能。 相似文献
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Ruby Chakraborty Mrunal Thatte Mark D. Soucek 《Journal of Coatings Technology and Research》2009,6(4):471-481
The effect of oil length of alkyds and substitution of siloxane backbone has been studied for alkyd–siloxane hybrids. A series
of nine alkyd–siloxane hybrids were synthesized by either varying the oil length of the alkyd or the siloxane backbone substitution.
Three linseed oil-based alkyds with either a long, medium, or short oil length were grafted with three hydride-terminated
siloxanes substituted with methyl, cyclopentyl, or cyclohexyl groups. A hydrocoupling reaction was used to couple the telechelic
siloxane with the hydroxyl functionality of the alkyds using Wilkinson’s catalyst. The reaction was monitored by the disappearance
of siloxane hydride signal using Fourier transform infrared. Characterization of siloxane–alkyd hybrids was performed using
1H-NMR, 13C-NMR, and gel permeation chromatography. The hybrids were formulated with a Co, Zr, and Ca drier package and auto-oxidatively
cured without using any solvent. The tensile, viscoelastic, and coating properties were evaluated for the cured films. The
crosslink density, flexibility, and reverse impact resistance were found to increase as a function of oil length. Tensile
modulus, elongation-to-break, glass transition temperature, drying time, and fracture toughness decreased with increase in
oil length. For the alkyd–siloxane hybrids, the mechanical and rheological properties were dependant on the size of the substituents.
The larger-sized cyclopentyl and cyclohexyl groups resulted in better mechanical and rheological properties than the methyl-containing
siloxanes. 相似文献
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Because of the relative ease to modify, functionalize, and synthesize polysiloxanes, these compounds offer interesting possibilities to greatly influence the properties of a catalytic system. These potentials are illustrated with three catalytic systems. In the first system, siloxane nanocages are shown to exhibit confinement effects by strongly modifying the protonation affinity of internal amine groups and by changing the activity and product selectivity in a reaction catalyzed by these groups. In the second example, the length of the siloxane backbone of a bis(pyridyl)siloxane ligand is shown to be critical both in stabilizing a Pd acetate complex catalyst in selective oxidation of benzyl alcohol, and in determining the dependence of the reaction rate on the pyridyl concentration in the reaction mixture. In the third example, polysiloxanes are shown to be useful in the preparation of a supported Pd catalyst in which the metal loading and particle size can be independently controlled. 相似文献
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George Stiubianu Maria Cazacu Alina Nicolescu Viorica Hamciuc Stelian Vlad 《Journal of Polymer Research》2010,17(6):837-845
Cellulose acetate was reacted with different amounts of 1,1,3,3-tetramethyldisiloxane in presence of Karstedt’s catalyst,
in solution, by using dry acetone as a solvent. A dehydrocoupling reaction between Si-H and C-OH groups with H2 evolving and the formation of Si-O-C bond occured, as proved by FTIR and NMR spectra, having as a result the crosslinking
of cellulose derivative. A model reaction was followed online by 1H NMR spectroscopy. Morphological changes as a result of the siloxane coupling to the cellulose derivative were emphasized
by Environmental Scanning Electron Microscopy (ESEM). The surface (water contact angle and water vapor sorption capacities)
and mechanical properties (breaking strength, breaking strain and Young modulus) of the networks processed as films were investigated
and the results were correlated with the reactants ratios. 相似文献
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γ-氯丙基三甲氧基硅烷季铵化反应规律探讨 总被引:6,自引:0,他引:6
探讨了γ-氯丙基三甲氧基硅烷与十八烷基二甲基叔胺季铵化反应中,无机碘化物与溶剂对反应速率的影响。通过定性分析反应中生成的白色沉淀以及拟合该反应速率常数,发现无机碘化物作为一种反应物参与了该季铵化反应,它与γ-氯丙基三甲氧基硅烷反应生成的高反应性γ-碘丙基三甲氧基硅烷加速了初期反应速率。在不同类型的溶剂中,该季铵化反应速率常数差别显著,一般来说反应速率随溶剂的介电常数越大而加快,但是苄醇偏离此规律比较远。并从热力学角度分析了溶剂对季铵化反应的影响。 相似文献