聚氨酯有机硅匀泡剂的研究及应用

综述了近年来有机硅表面活性剂聚二甲基硅氧烷、聚醚改性聚硅氧烷作为聚氨酯泡沫塑料匀泡剂的研究进展,重点介绍了其主要品种S i─C型聚醚改性聚硅氧烷在无溶剂工艺、催化剂的制备及聚醚配方优化等方面的进展,指出目前提高国产软泡匀泡剂的产品质量是聚氨酯有机硅匀泡剂研究的发展方向。     

聚氨酯泡沫用有机硅匀泡剂的合成及应用探讨

对当前匀泡剂的发展进行了分析,针对有机硅匀泡剂在聚氨酯泡沫生产中发挥的作用以及实际应用特点进行了探讨。结合实际状况对我国聚氨酯泡沫合成中有机硅匀泡剂的应用发展提出了一些建议。     

聚氨酯泡沫用有机硅匀泡剂

本文对聚二甲基硅氧烷撑嵌段共聚物等有机硅匀泡剂的制法、表面活性以及在聚氨酯泡沫体形成中的作用和应用作了简明的论述。同时,也提出了有机硅匀泡剂的今后发展方向。     

有机硅匀泡剂在聚氨酯硬泡中的应用评价

比较了添加自制有机硅匀泡剂与国内外主流匀泡剂的聚醚组合料的乳化性能和流动性能,及其聚氨酯硬泡的吸水率和尺寸稳定性。结果表明,对于环戊烷发泡体系,添加自制有机硅匀泡剂XHG-295和国内外主流匀泡剂的聚醚组合料的乳化性能和流动性能及其聚氨酯硬泡的吸水率和尺寸稳定性都接近;对于HCFC-141b发泡体系,添加自制有机硅匀泡剂XHG-299和国内外主流匀泡剂的聚醚组合料的乳化性能和流动性能及其聚氨酯硬泡的吸水率和尺寸稳定性都接近。XHG-295和XHG-299能达到家电组合料和保温板材组合料生产对匀泡剂的质量要求。     

粗孔匀泡剂HRSi-2在聚氨酯软泡中的应用

介绍了粗孔匀泡剂HRSi-2应用于普通软泡体系中,制备类似于高回弹泡沫制品的技术。对使用HRSi-2、普通软泡匀泡剂G-580及高回弹匀泡剂WD5333制备的相同密度的软质聚氨酯泡沫制品及高回弹泡沫制品的外观和泡沫性能进行了对比。结果表明,采用粗孔匀泡剂HRSi-2的聚氨酯软泡制品具有高回弹软泡的粗孔、乱孔的特点,综合性能介于普通软泡与高回弹软泡之间。     

软泡匀泡剂D-529的合成及其性能研究

以含氢硅油与不饱和聚醚的硅氢加成反应合成了软泡匀泡剂D-529,并对这种醚基封端的硅碳型聚氨酯软泡匀泡剂D-529的合成及其某些性能进行了研究。结果表明,在结构上与美国L-580匀泡剂属同一类型,发泡性能与L-580相似,并且用量小、活性高。     

H—420软泡匀泡剂

合成了软泡用匀泡剂Ｈ－４２０。讨论了匀泡剂的聚硅氧烷链段聚合度、聚硅氧烷与聚醚链段数之比等因素对其发泡过程中性能的影响,发泡试验结果表明,Ｈ－４２０对辛酸亚锡用量适应范围较宽,该匀泡剂已在软泡生产中应用,生成的泡沫,其主要性能与采用进口的相当。     

改进低密度鞋底原液工艺性能的添加剂

研究了硅氧烷-聚醚共聚物匀泡剂的结构组成对低密度微孔聚氨酯鞋底料性能的影响，介绍了新型匀泡剂DC3042及DC3043在低密度鞋底料中作用，其中DC3042可改善泡孔结构及制品表现质量，而DC3043具有改善尺寸稳定性的作用，两种复配可得到满意的效果。还介绍了催化剂Dabdo1027及Dabco1028与现有催化剂复配使用可缩短脱模时间或延长乳白时间。     

硅碳型软泡匀泡剂合成及其性能研究

对一种醚基封端硅碳型聚氨酯软泡匀泡剂Ｈ－４２０的合成，发泡性能进行了研究并与同类匀泡剂比较性能。结果表明，在结构上它与美国Ｌ－５８０匀泡剂属同一类型，发泡性能也与Ｌ－５８０相近。     

低挥发有机硅匀泡剂在聚氨酯软泡中的应用评价

研究了4种有机硅匀泡剂对聚氨酯软泡中的挥发性有机化合物(VOC)和泡沫性能的影响。结果表明,采用相同的配方,与同类匀泡剂相比,分别使用低散发性匀泡剂BL-585LF和BL-8008NA制备的聚氨酯普通软泡和慢回弹泡沫具有较低的VOC、更好的舒适性和压缩永久变形,并且制得的普通软泡有更好的回弹性。     

特殊结构的有机硅表面活性剂(续)

介绍了阴离子型有机硅表面活性剂、含酚基或芳氨基的聚醚改性硅油、反应性聚有机硅氧烷/聚内酯共聚物、含糖基的有机硅表面活性剂的特点、结构、合成方法及应用。     

Experimental Study on Foam Properties of Mixed Systems of Silicone and Hydrocarbon Surfactants

Silicone surfactants are inevitably involved in industrial applications in combination with hydrocarbon surfactants, but properties of the mixtures of silicone and hydrocarbon surfactants have received little attention, especially foam properties of the mixtures. In this study, aqueous solutions of respective binary mixtures of a nonionic silicone surfactant with anionic, cationic, and nonionic hydrocarbon surfactants were prepared for evaluation of their foam properties. Surface tension of aqueous solutions of the mixtures were measured with the maximum bubble pressure method. Foaming ability and foam stability of the mixtures were then evaluated with the standard Ross–Miles method. The findings show that the addition of the silicone surfactant results in a decrease in surface tension for aqueous solutions of the hydrocarbon surfactants. The critical micelle concentration (CMC) of the hydrocarbon surfactants is also changed by the additive silicone surfactant. Additionally, clear foam synergistic effects were observed in the mixtures of silicone and hydrocarbon surfactants, regardless of the ionic types of the hydrocarbon surfactant. The foam stability of the hydrocarbon surfactant was shown to generally improve with the increasing concentration of the silicone surfactant. Even so, aqueous solutions of different ionic hydrocarbon surfactants in the presence of the silicone surfactant will give different foam stabilities. The results of the present study are meant to provide guidance for the practical application of foams generated by the mixtures of the silicone and hydrocarbon surfactants.     

Open cell poly(vinyl chloride) foams by mechanical frothing of plastisols

PVC plastisols were formulated with silicone surfactant, mechanically shipped to form froths, and oven-fused to form open-cell foams. These were much softer than conventional chemically-blown foams which contain mixtures of open and closed cells. Increasing plasticizer content and decreasing foam density also had the expected softening effects on foam properties.     

聚醚型有机硅表面活性剂的合成与应用

简述了有机硅表面活性剂结构及其性能和功效 ,对聚醚型有机硅高分子表面活性剂的合成方法与研究进展做了综述 ,并介绍了它们在纺织、日化、农药、化妆品、消泡与匀泡、造纸等领域的应用情况     

Development of water‐blown bio‐based thermoplastic polyurethane foams using bio‐derived chain extender

Water‐blown bio‐based thermoplastic polyurethane (TPU) formulations were developed to fulfill the requirements of the reactive rotational molding/foaming process. They were prepared using synthetic and bio‐based chain extenders. Foams were prepared by stirring polyether polyol (macrodiol), chain extender (diol), surfactant (silicone oil), chemical blowing agent (distilled water), catalyst, and diisocyanate. The concentration of chain extender, blowing agent, and surfactant were varied and their effects on foaming kinetics, physical, mechanical, and morphological properties of foams were investigated. Density, compressive strength, and modulus of foams decrease with increasing blowing agent concentration and increase with increasing chain extender concentration, but are not significantly affected by changes in surfactant concentration. The foam glass‐transition temperatures increase with increasing blowing agent and chain extender concentrations. The foam cell size slightly increases with increasing blowing agent content and decreases upon surfactant addition (without any dependence on concentration), whereas chain extender concentration has no effect on cell size. Bio‐based 1,3‐propanediol can be used successfully for the preparation TPU foams without sacrificing any properties. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Sequential nature of the exothermic reactions leading to the formation of flexible polyurethane foams

The exotherms of the reactions leading to the formation of polyurethane foams were measured. The inflection points of the exotherm curves were made evident by continuous differentiation with respect to time. The position and magnitude of the inflection points demonstrated the sequential nature of the reactions. The effects of the functionality of the polyol, the concentrations of the tin and amine catalysts, and the silicone surfactant are discussed.     

Microcellular foaming of silicone rubber with supercritical carbon dioxide

In spite of great concern on the industrial application of microcellular silicone rubber foams, such as in electric and medical devices, only a few works can be found about the foaming of silicone rubber. In this study, microcellular silicone rubber foams with a cell size of 12 μm were successfully prepared with curing by heat and foaming by supercritical CO₂ as a green blowing agent. The microcellular silicone rubber foams exhibited a well-defined cell structure and a uniform cell size distribution. The crosslinking and foaming of silicone rubber was carried out separately. After foaming, the silicone rubber foam was cross-linked again to stabilize the foam structure and further improve its mechanical properties. Foaming process of cross-linked silicone rubber should be designed carefully based on the viscoelastic properties because of its elastic volume recovery in the atmosphere. The basic crosslinking condition for small cell size and high cell density was obtained after investigating the rheological behavior during crosslinking.     

特殊结构的有机硅表面活性剂

介绍了聚醚改性支链硅油、乙烯氧基聚醚改性硅油、聚醚封端的长链烷基硅油、甘油醚与聚醚共改性硅油、含甜菜碱基的两性有机硅表面活性剂的性能、结构及合成方法。     

Surfactant Crystals as Stimulable Foam Stabilizers: Tuning Stability with Counterions

The demands on foam stability are variable and changing, which is why design of foams that are both ultrastable and stimulable is important. We study foams stabilized using surfactant particles made through precipitation of sodium dodecyl sulfate with alkali chlorides. We have previously shown that depending on the concentrations of surfactant and salt, the foams can be ultrastable or age like common surfactant foams. We now show that the adsorption of surfactant crystals changes with the type of salt added and how the crystals are made, as well as the surfactant concentration. We see differences in foam stability if the crystals are made prior to foaming or if they are formed concomitantly with foaming. The adsorption of the crystals is improved if the crystals are made during generation, possibly because of their smaller size. The foams destabilize when heated above the Krafft boundary. We show that through tuning the surfactant concentration and salt type or concentration, we can modulate the melting temperature, and hence the destruction temperature of foam between 22 and 50 °C. Precipitated surfactant particles are versatile alternatives to stabilize ultrastable and stimulable foams.