甲基苯基乙烯基硅油的制备与性能

以二甲基乙烯基乙氧基硅烷、二苯基二甲氧基硅烷和八甲基环四硅氧烷为原料,通过水解缩合反应制备了甲基苯基乙烯基硅油。考察了二甲基乙烯基乙氧基硅烷质量分数、缩合反应温度和缩合反应时间对产物性能的影响。并通过优化实验条件,合成了黏度5 600~6 700 m Pa·s、折射率1.545~1.555的甲基苯基乙烯基硅油,可用于LED有机硅封装材料。     

甲基二苯基封端硅油的制备及其热性能研究

以二甲基四苯基二硅氧烷为封端剂、八甲基环四硅氧烷或甲基苯基混合环体为原料，采用阴离子开环聚合法制备了甲基二苯基封端的二甲基硅油和甲基二苯基封端的甲基苯基硅油；测量了空气和惰性气氛下硅油的动态TGA数据，并与三甲基硅基封端的二甲基硅油进行了比较。结果表明，随着硅油中苯基摩尔分数的提高，甲基二苯基封端的二甲基硅油在空气和氮气气氛中的热稳定性有所提高；甲基二苯基封端的甲基苯基硅油在空气和氮气气氛中的热稳定性均得到较大程度的提高，苯基摩尔分数为17．38％的硅油在氮气中、且质量损失率为10％时的温度提高了75℃，苯基摩尔分数为7．56％的硅油在空气中、且质量损失率10％时的温度提高了74℃。     

高苯基含量硅树脂阻燃剂

华南理工大学的王瑜润等人以苯基三乙氧基硅烷、二苯基二甲氧基硅烷和二甲基二乙氧基硅烷为原料，在0．1mol／L的稀盐酸催化下水解缩聚制成具有阻燃性能的高苯基含量硅树脂。研究发现，当硅树脂中的苯基摩尔分数为80．0％～90．0％、     

缩合法制备高黏度苯甲基硅油的研究

<正>以二苯基二甲氧基硅烷和二甲基二乙氧基硅烷为原料,制备了高黏度的苯甲基硅油,并研究了原料配比和聚合时间对苯甲基硅油折光率和黏度的影响。研究表明:随二苯基二甲氧基硅烷用量增大,苯甲基硅油的折光率升高;当聚合时间小于2 h时,黏度随时间的增大而增大;当聚合时间大于2 h时,苯甲基硅油的黏度趋于稳定。0前言苯甲基硅油是甲基硅油中部分甲基被苯基取代后的产物,具有耐高温、耐辐照、润滑性和高折射率等优点,在航空航天、船舶汽车、电子电气、轻工     

高折射率、长寿命LED灌封胶的制备及性能

以甲基苯基混合环体、八甲基环四硅氧烷、四甲基四乙烯基环四硅氧烷、四甲基二乙烯基二硅氧烷等为原料制得甲基苯基硅油;以苯基三氯基硅烷、二苯基二氯硅烷、二甲基二氯硅烷和二甲基乙烯基氯硅烷等为原料,制得甲基乙烯基苯基有机硅树脂;以二苯基二甲氧基硅烷、苯基三甲氧基硅烷、四甲基环四硅氧烷为原料制得苯基交联剂。按甲基乙烯基苯基硅油、甲基苯基乙烯基硅树质量比和n Si—H/n Vi筛选出符合LED芯片封装基本要求的灌封胶,其折射率为1.5441,操作黏度(25℃)4 000~5 500 m Pa·s,固化后的初始邵尔D硬度为33~37度,可见光(550 nm)透光率大于85%。耐热老化性能测试研究表明,150℃热老化1 000 h后,硬度增幅为5度,无黄变现象,在550 nm的透光率大于80%。进一步的光通量测试研究表明,点灯测试1 000 h后,该灌封胶的光衰2%。表明该款灌封胶具有高折射率和较长的应用寿命。     

苯基含量、链节种类对甲基苯基硅油性能的影响

分别以甲基苯基环硅氧烷混合物、八苯基环四硅氧烷为原料,与二甲基环硅氧烷混合物在碱性催化剂的条件下,合成了甲基苯基硅油,研究了不同种类苯基链节、含量对甲基苯基硅油黏度、密度、折射率等性能的影响。研究表明,该方法合成的甲基苯基硅油的苯基摩尔分数在5%~50%范围内可调,苯基链节种类、含量会直接影响其黏度、密度、折射率等指标。苯基摩尔分数提高,以上三项指标相应上升。苯基链节种类会影响硅油分子链的柔性,当苯基同时位于同一链节时会增加分子链刚性。宏观表现为相同苯基摩尔分数下,相比于以甲基苯基环硅氧烷混合物合成的甲基苯基硅油,以八苯基环四硅氧烷合成的甲基苯基硅油的黏度随苯基摩尔分数提高呈现更加快速的上升趋势。     

氨基改性甲基苯基硅油的制备与应用

以二苯基二甲氧基硅烷、N-(β-氨乙基)-γ-氨丙基甲基二甲氧基硅烷与线性体为原料,四甲基氢氧化铵为催化剂,通过酯交换和缩聚反应合成了氨基改性甲基苯基硅油,考察了催化剂用量、反应温度时间,氨值和苯基含量对产品性能的影响,确定了最佳工艺条件,用于织物后整理,能赋予织物良好的柔软性,滑爽性和光泽度。     

α,ω-乙烯基封端甲基苯基聚硅氧烷的制备

以甲基苯基二甲氧基硅烷为原料,采用水解-聚合法制备了不同摩尔质量的α,ω-二乙烯基甲基苯基硅油;并进行了动力黏度、乙烯基含量、折射率、挥发分等性能表征。结果表明,以甲基苯基二甲氧基硅烷为原料,生产成本低,反应单一,该产品杂质含量低,后处理简单。同时,从甲基苯基水解物出发,可以制备多种官能团封端的苯基硅油,大大提高了水解物的利用率并可得到实用性及性能齐全的产品。产品折射率均在1.51以上,最高可达1.55。该乙烯基封端甲基苯基硅油的透光率也完全符合作为LED封装材料的要求。样品在固化后折射率高、透光性好,有较强的耐溶剂、耐水性及耐辐射性,具有耐高温性好、不增粘等优点。所制成的产品具有耐老化性强、抗紫外线性佳及长期使用无变黄等优异性能。     

3，5-双（三氟甲基）苯基硅油的合成及性能研究

以3,5-双(三氟甲基)溴苯和甲基三甲氧基硅烷为原料,通过格氏反应和取代反应制备了一种含氟有机硅单体3,5-双(三氟甲基)苯基甲基二甲氧基硅烷;然后将其与二甲基二甲氧基硅烷共水解、平衡聚合制得3,5-双(三氟甲基)苯基硅油.通过FT-IR、1H NMR、19F NMR和元素分析等对含氟有机硅单体和氟硅油进行了表征.含氟硅油的表面张力为20.5 mN/m,大于二甲基硅油(19.0 mN/m).以硅油质量损失10%时的热分解温度来表征材料的热稳定性,二甲基硅油为232.3 ℃,含氟苯基硅油为265.2 ℃,表明含氟苯基硅油的热稳定性比二甲基硅油优越.     

甲基苯基硅油合成反应的影响因素

以甲基苯基二甲氧基硅烷和四甲基二乙烯基二硅氧烷为原料,通过水解缩合反应制得甲基苯基硅油。采用正交实验研究了催化剂、水解反应时间、水的用量、缩合反应温度和时间等对甲基苯基硅油合成反应的影响。结果表明,缩合温度是反应最主要的影响因素,且聚合物的平均摩尔质量可通过封端剂用量来控制。最佳合成条件为:KOH作催化剂、用量1.5%,水与甲基苯基二甲氧基硅烷的量之比为1.7∶1,原料在72℃水解回流反应2 h后,于110℃缩合反应5 h。在此条件下,可制得高透明、高折射率性质稳定的甲基苯基硅油,能用于LED封装材料等领域。     

Evaluation of emu oil extraction methods and their effects on physical and rheological behavior

In this study we evaluated the efficiency of six extraction methods for emu fat based on the quantification of yield, color, density, refraction index, and rheological behavior. Both physical methods (Bain Marie, rotary evaporator, fusion, ultrasound, and microwave) and chemical methods (solvents) were evaluated. Oil properties were compared with commercial emu oil as a reference. Solvent‐based extraction produced the greatest yield (72.8%). Among the physical methods, the greatest yield was produced by the ultrasound method (42.8%). In general, properties were similar to those reported for vegetable oils. The rotary evaporator method showed the greatest difference in total color (ΔE) in comparison with a commercially‐produced reference, while the fusion method showed the smallest ΔE. No statistically significant differences were found between the density and refraction index of the treated samples and those of the reference. Kinematic viscosity increased significantly in samples extracted via microwave method. All samples displayed pseudoplastic behavior. The data showed a good fit to the power law model (R² > 0.90). The consistency coefficient and flow behavior index were determined for all methods. Practical applications: Therapeutic applications for oil have been posited for emu oil. In pharmaceutical products, oils are used as emollients and as carriers for medicinal substances. The practical importance of an oil depends on its physical properties, thus a thorough understanding of those physical properties is very important for identifying potential applications. These properties are affected by the extraction method employed; the present paper evaluates the effects of a range of extraction methods on yield efficiency, as well as physical and rheological properties. Novel extraction methods such as ultrasound and microwave are also evaluated in this study.     

THE INDEX OF REFRACTION OF SOME SODA-LIME-SILICA GLASSES AS A FUNCTION OF THE COMPOSITION1

Twenty-one soda-silica and twenty-one soda-lime-silica glasses were made in platinum crucibles and the index of refraction and chemical compositioii of each glass were determined. From the data obtained equations were derived and a diagram was prepared showing the relations between index of refraction and composition of these glasses. The diagram makes it possible to predict with considerable accuracy (1) the index of refraction of any glass in the range of compositions considered, from its composition. and (2) the cwpositions of the various glasses which have the same index of refraction. Some evidence is presented indicating that index of refraction of the soda-silica glasses may be a simple function of certain soda-silica compounds which may be present in glass.     

甲基三氯硅烷的综合利用

简述了甲基三氯硅烷在甲基三甲氧基硅烷、甲基三乙氧基硅烷、甲基三乙氧然硅烷、甲基硅树脂、甲基苯基硅树脂、甲基硅酸钠等有机硅产品制备中的应用,以及这些有机硅产品的用途。     

Optische Methoden zur Charakterisierung von hochpolymeren Fasern. 1. Methodik der Interferenzmikroskopie

Density and orientation describe, besides other characteristics, the structure of high polymers. They can be obtained as a function of the radius by measurement of the refraction index of the fibre. The influence of refraction of light on the obtained index of refraction n(r) is demonstrated by an optical model of the fibre. For fibres having a radius R < 30 μm and changes in the refraction index < 0.02 the influence of refraction is less than ± 0.0002 and therefore of no significance for most textile fibres. Important is the exact adaption of the refraction index of the embeding medium to the margin of the fibre. The computed index at the margin of the fibre takes always the refraction index of the embeding medium. An incorrect adaption can be traced up to 0.2·R into the fibre. A spline function used for the approximation of the relative displacement of interference fringes gives the opportunity to calculate extreme variations in refractive index, this is demonstrated using hollow fibres filled with paraffin-oil. Using a HeNe-laser interference-holographie became possible.     

An optical approach for identifying the nature and the relative 3D spatial position of components of complex structures formed in multiphase dispersion systems

This paper describes a novel method that makes possible the identification of the nature and the 3D relative spatial position (free or embedded) of the components of complex structures (oil drops, water droplets, air bubbles and multiphase drops) formed in dispersions occurring in fermentation systems, without disturbing (either chemically or physically) the dispersion. Using the refraction index differences between each phase and the image-forming properties of the complex objects formed in addition to the relative size of the bright part of the spheres, it was possible to determine the nature of each type of structure, as well as to discern whether these structures were located inside or outside of the multiphase oil drops. This method allowed determining unequivocally that the small droplets observed within the complex oil drops are part of the aqueous phase and are trapped inside the oil drops, together, in some cases, with air bubbles.     

涤纶短纤维含油率测试方法的比较

采用了萃取称重法、萃取折射率法、快速法、核磁共振法测定了对涤纶短纤维的含油率进行了比较。结果发现,萃取称重法、萃取光折射率法、快速法测定不同油剂的含油率时,应根据油剂的溶解特性,选择不同的溶剂萃取。对于阴离子型烷基磷酸酯钾盐油剂宜选择苯/甲醇(体积比1:1)的混和溶剂。4种分析方法中,萃取称重法测定涤纶短纤维的含油率结果偏高;快速法测定的结果偏低;萃取光折射率法和核磁共振法测定涤纶短纤维的含油率结果准确,精密度较高,能正确反映纤维上油情况。     

不同氟含量氟碳树脂的折射率及实用性研究

采用氟烯烃与丙烯酸酯共聚的方法合成了氟含量(质量分数)分别为20%,35%的氟碳树脂,采用含氟丙烯酸酯直接共聚的方法合成了氟含量为50%的氟碳树脂。采用傅里叶变换红外光谱分析氟含量为20%和35%的氟碳树脂结构,结果表明合成的这两种氟碳树脂中含有氟基团;采用椭偏仪测试了树脂的折射率,结果表明3种氟碳树脂的折射率均低于丙烯酸树脂,氟含量为20%和35%的氟碳树脂的折射率相差不大,而氟含量为50%的氟碳树脂的折射率相对较高;采用X射线光电子能谱仪分析了3种氟碳树脂涂覆膜正反面的氟元素分布情况,结果表明随着氟含量的增加,膜正面氟含量逐渐增加至饱和,继续增加氟含量只会增加膜反面的氟含量;最后分别测试了树脂的抗污性能和附着力,结果表明氟含量为20%及35%的氟碳树脂在具有较低折射率的同时兼具良好的附着力及抗污性能。     

EFFECT OF PARTICLE SIZE AND INDEX OF REFRACTION ON REFLECTANCE*

The effect of particle size on the reflectance of thin semitransparent layers, such as enamels, was studied by using mixtures containing opacifying particles of definite sizes in an oil of known index of refraction. The mixtures were applied on a black glass plate, and the reflectance was measured. The coefficient of scatter per unit surface of the particles was calculated and was found to decrease slowly as the particle size decreased. On the other hand, for the range of sizes studied, the reflectance of the semitransparent layer increased rapidly as the particle size decreased.     

Carbonization of petroleum binders. 2. Oils from carbonization of petroleum binders

Changes of composition, structure, and contents of some functional groups, of oils from petroleum binders, in relation to temperature of carbonization from about 710 K to 1200 K have been investigated. Oils from carbonization of petroleum binders are of hydrocarbon type, and their elemental compositions are almost independent of carbonization temperature. During the thermal decomposition of these binders, about 75–80 wt % of gaseous and vapour products are emitted. As carbonization temperature increases, molecular weights of the oils increase from about 250 to about 290; their density, index of refraction, and molar refraction increase. Structural analysis of the oils showed that they contained about 30% of cyclic hydrocarbons (aromatic and cycloalkane) as well as alkanes. The number of rings in the average structural unit of oil increases with increase of carbonization temperature, especially the number of aromatic rings. About 60–70 vol % distills before 633 K under atmospheric pressure; the distillate is paraffinic, while the residue after distillation is aromatic-alicyclic. Oils from carbonization of P-70 asphalt have similar compositions and chemical natures, but lower molecular weights, than oils from carbonization of residues after vacuum distillation of crude oil. Oils from carbonization of pitch are decidedly aromatic.     

SURFACE LAYER OF SHEET GLASS*

This research was conducted to obtain evidence of the nature of the fire polish on sheet glass. Three measurements were made on each sample as follows: (1) The deviations from Fresnel's reflection laws, (2) a measurement based on the Pfund method of determining the apparent Brewsterian angle as compared to that calculated from the index of refraction of the glass, and (3) the true index of refraction by a prism method in which the samples were cut and ground to 60-degree prisms. These measurements showed that freshly drawn sheet glass probably has a crystalline layer several molecules thick on the surface. The layer has a high index of refraction, but this is counteracted quickly by water absorption if the glass is dampened slightly or is exposed to the atmosphere.