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首页> 外文会议>API (Alliance for the Polyurethanes Industry) Polyurethanes Technical Conference >Compatibilizers in Polyurethane Foam for the Construction Industry. Concept, Use and Benefits
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Compatibilizers in Polyurethane Foam for the Construction Industry. Concept, Use and Benefits

机译：建筑行业聚氨酯泡沫中的相容剂。概念，用途和好处

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Present foam formulations in the construction industry, especially in the panel and block production for this segment, typically involve the mixing of incompatible liquids. In the polyol blend the current blowing agents are used in levels far above their solubility. Hydrocarbons such as the isomers of pentane have a low solubility in the polyols so that difficulties in the production of foams are often related to insufficient mixing or phase separation occurring too early. Furthermore, the low boiling point of many blowing agents adds to problems in the form of frothing of the raw material mix at laydown. On the isocyanate side the situation is similar. The polyol(mix) itself and also the hydrocarbons such as iso and n-pentane are only soluble in small amounts. Above solubility limits, emulsions in the isocyanate are formed. This can also lead to typical problems related to insufficient mixing: wide droplet size distribution or early phase separation. This paper will discuss processing additives acting as compatibilizers in mixing the raw materials of rigid PU foam. We look separately at emulsification of raw materials and stabilization of cells. While the latter is based on surface tension reduction of the liquid-gas interfacial layer often accomplished with silicone based surfactants, the former point can be successfully addressed using additives enhancing the emulsion formation by bridging the liquid-liquid interfacial layers. With their presence at these interfaces, the additives can influence the time to form the emulsion and the stability of the droplets in the continuous phase. The additives also have an influence on the rheology of the mix, the rate of evaporation of blowing agents and to some extent on the kinetics of the foaming reaction. Ultimately, the physical properties of the foam are improved. Besides the quality aspect, we have also identified an economic advantage: the new products can result in a more efficient use of formulation components such as catalysts and blowing agents leading to possible savings.
机译：建筑行业中，特别是在该领域的面板和砌块生产中，目前的泡沫配方通常涉及不相容液体的混合。在多元醇共混物中，目前的发泡剂的用量远高于其溶解度。碳氢化合物（例如戊烷的异构体）在多元醇中的溶解度较低，因此生产泡沫的困难通常与太早发生的混合不足或相分离有关。此外，许多发泡剂的低沸点以沉积时原料混合物起泡的形式增加了问题。在异氰酸酯方面，情况类似。多元醇（混合物）本身以及诸如异戊烷和正戊烷之类的烃仅是少量可溶的。超过溶解度极限，形成异氰酸酯中的乳液。这也可能导致与混合不充分相关的典型问题：液滴尺寸分布较宽或早期相分离。本文将讨论在混合硬质PU泡沫原料时用作增容剂的加工助剂。我们分别着眼于原料的乳化和细胞的稳定。尽管后者是基于通常用硅氧烷基表面活性剂降低液-气界面层的表面张力的方法，但是前者可以使用通过桥接液-液界面层来增强乳液形成的添加剂来成功解决。由于它们在这些界面处的存在，添加剂会影响形成乳液的时间和液滴在连续相中的稳定性。添加剂还影响混合物的流变性，发泡剂的蒸发速率，并在一定程度上影响发泡反应的动力学。最终，泡沫的物理性能得到改善。除了质量方面，我们还发现了经济优势：新产品可以使配方成分（例如催化剂和发泡剂）的使用效率更高，从而可以节省成本。

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