Plastic molded unit for producing pipelines, comprises a two-layered structure in a cross-section, an inner layer and a barrier layer

摘要

The plastic molded unit for producing pipelines, comprises a two-layered structure in a cross-section, an inner layer and a barrier layer. The inner layer is contacted with a medium guided in the pipeline and contains additives for protecting polymer chains against aggressive media. The barrier layer enfolds the inner layer in all sides and decreases the migration of the additives from the inner layer. The plastic material partially shows a hexagonal crystal structure. The barrier layer contains glass fibers, glass balls and/or glass flour, and/or additives. The plastic molded unit for producing pipelines, comprises a two-layered structure in a cross-section, an inner layer and a barrier layer. The inner layer is contacted with a medium guided in the pipeline and contains additives for protecting polymer chains against aggressive media. The barrier layer enfolds the inner layer in all sides and decreases the migration of the additives from the inner layer. The plastic material partially shows a hexagonal crystal structure. The barrier layer contains glass fibers, glass balls and/or glass flour, and/or additives and is covered by an outer layer of the molded unit. The outer layer and the barrier layer are produced from same polymer. The molded unit has a second barrier layer for reduction of the migration of the additives from the inner layer arranged next to the first barrier layer from crystalline and/or nucleated polymer. The inner layer contains metal deactivators, chlorine acceptors, acid acceptors, radical inhibitors, UV-stabilizers, processing stabilizers and/or long-term stabilizers as additives.