Process for the production of expanded reticulated polyethylene, comprising the steps of:
to melt an ethylene polymer selected among ethylene homopolymers, ethylene copolymers with alpha-olefins, copolymers of ethylene with conjugated diolefins, and related mixtures;
to homogenize said ethylene polymer, in the molten state, with a reticulating agent and an expanding agent, until a homogeneous mixture is obtained;
to give to said homogeneous mixture a solid parallelepiped shape by means of extrusion and subsequent cooling, or by means of moulding:
to place the solid parallelepiped shaped body inside an air-tightly closed container; to pressurize the container by an inert gas and to heat the parallelepiped shaped body to a temperature higher than the decomposition temperature of the reticulating agent and of the expanding agent contained therein; in the absence, or in the substantial absence of expansion;
to depressurize the container, allowing the shaped body to expand to an end volume smaller than the volume of the container;
to recover the expanded reticulated item from the container.
生产发泡网状聚
乙烯的工艺,包括以下步骤
熔化选自
乙烯均聚物、
乙烯与α-烯烃共聚物、
乙烯与共轭二烯烃共聚物及相关混合物的
乙烯聚合物;
在熔融状态下,用网状剂和膨胀剂均化所述
乙烯聚合物,直至得到均匀混合物;
通过挤压和随后的冷却,或通过模塑,使所述均质混合物形成实心平行管状:
将实心平行管状体置于一个密闭容器内;用惰性气体对容器加压,并将平行管状体加热到高于其中所含网状剂和膨胀剂分解温度的温度;在没有膨胀或基本没有膨胀的情况下;
对容器减压,使定型体膨胀到小于容器容积的最终容积;
从容器中回收膨胀后的网状物。