摘要:
The invention provides molded polyamide articles and a process for making the same. The molded polyamide articles consist substantially of tetramethylene adipamide units, the articles having an increased crystallinity expressed as a first melting enthalpy which is at least 30 Joules per gram higher than a second melting enthalpy determined after subsequent solidification of the polyamide. The process comprises shaping the polyamide from the melt, cooling the resulting polyamide article, and heat treating the article in an inert gas atmosphere at a temperature of 220.degree. C. for 0.25 to 24 hours.
摘要:
A rotational molding process for manufacturing objects having a foamed plastic substrate adhered to an outer polyolefin coating layer, and having improved adhesion therebetween comprising the combination of steps of: preparing a first outer coating layer of a stabilized polyolefin; forming a second inner layer of an at most slightly stabilized polyolefin contiguous with and on the interior surface of said first outer layer; and thereafter introducing a foamable plastic material onto the interior surface of said second layer and foaming said plastic material thereagainst thereby the foamed plastic is bonded to said second interior surface.
摘要:
A polyolefin composition having improved adhesion to foamable plastic substrates, comprising an intimate mixture of about 20% to about 99.5% by weight of a first stabilized polyolefin powder and from about 0.5% to about 80% by weight of a second at most slightly stabilized polyolefin powder, said second powder having a crystalline melting point which is at least 1.degree. higher than that of said first powder and wherein said second powder has the ability to be oxidized under process conditions.
摘要:
The invention relates to a process for melt-shaping a polymer composition wherein the constituent components for the polymer composition are supplied directly to the shaping device in the form of a mixture of granules on or in which the constituent components are present. The granule mixture contains at least 3 granule-fractions containing the matrix polymer that differ in composition.The invention also relates to the granule mixture suitable for the melt-shaping process, the installation for the preparation and the process for preparing the granule mixture. The process results in a greater reproducibility and in articles with improved properties.
摘要:
The invention relates to a thermoplastic moulded printed circuit board consisting substantially of polyamide 4.6. Preferably use is made of a multilayer structure, of which at least one layer contains reinforcing filler material.
摘要:
The invention relates to a polyamide composition with improved stability in contact with oil at elevated temperatures. The polyamide composition with superior stability characteristics has been obtained by the incorporation in the polyamide composition of a small amount of an alkaline inorganic material. Preferably the polyamide is nylon 4.6.
摘要:
A multi-layer polyamide moulded articles having, inter alia, improving mechanical properties, one layer of which is reinforced with filler and covered at least on one side with a non-reinforced polyamide layer and of which the polyamide substantially consists of nylon 4,6 and the filler is non-fibrous.
摘要:
A polyolefin composition having improved adhesion to foamable plastic substrates, comprising an intimate mixture of about 20% to about 99.5% by weight of a first stabilized polyolefin powder and from about 0.5% to about 80% by weight of a second at most slightly stabilized polyolefin powder, said second powder having a crystalline melting point which is at least 1.degree. higher than that of said first powder and wherein said second powder has the ability to be oxidized under process conditions.