摘要:
Solution of UHMWPE in an organic solvent having a total PE concentration of at least 15% by weight and in which some of the PE present is crosslinked.
摘要:
A polarizer including a polarization grating comprising a polarization sensitive photo-alignment layer and a liquid crystal composition arranged on said photo-alignment layer. An alignment pattern, corresponding to the polarization pattern of a hologram, is recorded in the photo-alignment layer, and the liquid crystal composition is aligned on the photo-alignment layer.
摘要:
A polarization grating comprising a polarization sensitive photo-alignment layer (2) and a liquid crystal composition (3) arranged on said photo-alignment layer is provided. An alignment pattern, corresponding to the polarization pattern of a hologram, is recorded in the photo-alignment layer, and the liquid crystal composition is aligned on the photo-alignment layer. As the origin for the alignment of the liquid crystal composition is a polarization hologram recorded in a photo-alignment layer, an essentially defect-free pattern can be obtained with this approach.
摘要:
A process for the manufacture of filaments, tapes and films that possess a shish-kebab morphology. This is effected in that for instance UHMW PE after extrusion is stretched at a temperature between the melting temperature (Tm) and a critical temperature (Tc) and subsequently cooled in stressed condition. The stretching rate is between 0.1 and 10 [sec.].sup.-1.
摘要:
A process is described for the preparation of highly stretchable high-molecular weight polyolefin gel articles and polyolefin gel articles prepared therefrom having combined high tensile strength and high modulus, wherein an initial shaped article of the polyolefin is exposed to or contacted with a swelling agent to form an intermediate swollen article, which is then converted to the gel state and then subsequently subjected to stretching at up to relatively high draw ratios.
摘要:
High strength and modulus articles, such as filaments, fibers, tapes, films, tubes, bars or profiles, are prepared by irradiating a solid, particular, lamellar, disentangled polyethylene with a Mw>4.times.10.sup.5, transforming this polyethylene above the melt temperature into an article, cooling said article to below the melting point and stretching it in several steps at rising temperature but below the melting point of the article.Advantages are i.a. the lower costs compared with the known processes, such as solid state extrusion or thermoreversible gelation.
摘要:
Thermosettable composition suitable for the production of endless objects without the use of continuous carrier material, whereby the composition comprises an epoxy resin or an unsaturated polyester and a high molecular weight thermoplastic polymer which has a weight-average molecular weight of at least 1,000,000 g/mol in an amount to make the composition spinnable, the amount ranging from at least 0.1% where the polymer has a molecular weight of 5,000,000 g/mol or more or less than 2% where the polymer has the weight-average molecular weight of 1,000,000 g/mol, the amount decreasing as the weight-average molecular weight increases.
摘要:
Thin self-supporting green compact, less than 25.mu. thick, containing an inorganic substance and as a binder a polymer with a weight average molecular weight of more than 400,000, which polymer in a suitable solvent can form a thermoreversible gel above room temperature, the volume fraction of the inorganic substance being more than 45% relative to the total amount of binder plus inorganic substance and a process to prepare such green compacts.
摘要:
An ultrastretchable polymer material is prepared starting from polyolefine particles with a low entanglement density and a weight average molecular weight (M.sub.w) higher than 400,000, the particles being densified to a coherent material together with a process auxiliary material at an elevated temperature, but below the melting point of the pure polyolefine.From this ultrastretchable material, objects with a high tensile strength and a high modulus can be produced by stretching it, for instance, at a temperature which is at most 70.degree. C. below the temperature at which the polyolefine melts under the prevailing conditions, if desired after removal of the process auxiliary agent present in it.
摘要:
Process for the manufacture of a polarizing film by drawing a polymer film containing a dichroic dye at a temperature above the glass transition temperature of the polymer, the polymer film consisting mainly of a semi-crystalline polyolefine and being drawn at a temperature below the crystalline melting point of the polyolefine, the dye being present in liquid form at that drawing temperature, and a polarizing dye-containing polyolefine film having a dichroic ratio of at least 15.