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一、温度对泡沫塑料形成的影响在讨论模温对泡沫塑料夹层结构质量的影响之前,先谈谈温度对硬质聚氨酯泡沫塑料(以下简称泡沫塑料)形成的影响。在聚氨酯泡沫塑料形成过程中,要经过几个阶段。首先,发泡剂产生的气体溶解在液相,气体溶解在液态介质中达到饱和,最后形成气泡,并从液态介质中分离出来。这一过程即通常所谓的“成核”过程。气泡的形成是一个产生新的气、液界面的过程。这个过程必然导致体系自由能的增加,即:ΔF=r·ΔA (1)式中:ΔF——自由能增量;
First, the temperature on the formation of foam Before discussing the impact of mold temperature on the quality of the foam sandwich structure, first talk about the temperature on the rigid polyurethane foam (hereinafter referred to as foam) the formation of. In the polyurethane foam formation process, going through several stages. First, the gas generated by the blowing agent dissolves in the liquid phase, the gas is saturated in the liquid medium, and finally bubbles form and separate from the liquid medium. This process is commonly referred to as the “nucleation” process. Bubble formation is a process that produces new gas and liquid interfaces. This process will inevitably lead to an increase of the free energy of the system, namely: ΔF = r · ΔA (1) Where: ΔF - increment of free energy;