摘要:
A laminate consists of a layer A of a polyolefin, reinforced with from 10 to 50% of glass fiber mats, and a metal layer D, which are bonded to one another by means of a mechanically adhesion-promoting layer B and an adhesive layer C. The adhesive is a thermoplastic polyurethane elastomer, preferably having a melting range of from 110.degree. to 250.degree. C. The laminates are used as automobile components, and as housings and containers.
摘要:
Pelletized materials based on at least one thermoplastically processable polymer, where the pellets have less than 10% of concave regions and otherwise are convex in every other region, this being determined by means of incident-light interference-contrast spectroscopy, by taking the average value for the ratios of the outline area to the entire outline area for an assembly of pellets.
摘要:
An apparatus intended for extruding thermoplastics and having at least one devolatilization orifice and, if desired, also at least one dewatering orifice, which has been equipped with a metal-wire-mesh composite sheet, with a finely perforated metal sheet, or with a slit diaphragm.
摘要:
Binders, impregnating agents and coating agents based on an aqueous dispersion of an amide-containing copolymer, wherein the copolymer contains recurring units of the general formula I ##STR1## where R is H and/or CH.sub.3, eliminate virtually no formaldehyde in use and may advantageously be used as binders for bonding nonwovens.
摘要:
A thermoplastic molding composition having reduced gloss sensitivity and no unpleasant odor is produced from a graft copolymer and a thermoplastic polymer. The graft copolymer is produced from a soft elastomeric particulate graft base obtained by emulsion polymerization of a conjugated diene alone or with a small amount of a monoethylenically unsaturated monomer, using an inorganic radical generating substance and a limited amount of chain transfer agent, upon which is grafted a vinyl aromatic monomer and acrylonitrile and optionally another monoethylenically unsaturated monomer using an inorganic radical generating substance while the use of a chain transfer agent is excluded. The thermoplastic polymer is a copolymer of a vinyl aromatic monomer and acrylonitrile and optionally an additional monoethylenically unsaturated monomer. The thermoplastic molding composition has a low level of unpleasant odor coupled with reduced gloss sensitivity and good mechanical properties.
摘要:
A polybutadiene latex is prepared by a process in which butadiene is polymerized by free radical emulsion polymerization in the presence of initiator and, if required, dispersants and further conventional assistants, the polymerization being carried out in the presence of reactive comonomers in such a way that the heat flow of 43 watt/kg solids content of the polymerization mixture is not exceeded. Owing to the presence of reactive comonomers, the reaction rate at the beginning of the reaction is increased, with the result that an overall flatter heat flow profile is obtained. A preferred reactive comonomer is styrene. Preferably, the process is carried out by a semi-batch procedure in which (a) in a first stage, a portion of butadiene and at least one portion of reactive comonomer in the form of an aqueous emulsion are initially taken with a thermal polymerization initiator and, if required, dispersants and further conventional assistants and the polymerization is initiated, (b) in a second stage, the remaining amount of butadiene and, if required, the remaining amount of reactive comonomer are added undiluted or in the form of an aqueous emulsion, if required with dispersants and, if required, further conventional assistants, as a feed.
摘要:
The invention relates to a method for producing caoutchouc particles (K) by means of emulsion polymerisation in the presence of an emulsifier and a polymerisation initiator. Said particles contain A) 80 to 100 wt. % of one or more conjugated diene monomers (A) in relation to (K) and B) 0 to 20 wt. % of one or more monoethylenically unsaturated comonomers (B) in relation to (K) in the polymerised form. The inventive method is characterised in that 1) a mixture (M1) containing water and an emulsifier is provided, 2) a mixture (M2) containing one or more monomers in the monomer or polymerised form selected from styrole, &agr;-methylstyrole, butadiene, n-butylacrylate, MMA and acrylnitrile and optionally comonomers is added, 3) polymerisation of the obtained mixture starts in the presence of a polymerisation initiator at temperature of 5 to 95° C., 4) a mixture (M3) containing 0 to 100 wt. % of the comonomers (B) in relation to (B) and 0 to 25 wt. % of the diene monomers (A) in relation to (A) is added, 5) a mixture (M4) containing the (remaining) diene monomers (A) and the (remaining) comonomers (B) is proportioned and polymerised and 6) polymerisation is terminated when there is conversion of more than 90 and less than 95% in relation to the sum of the monomers.
摘要:
In a process for precipitating microsuspension polymers from a suspension comprising them, a polymer dispersion prepared by emulsion polymerization is added to the suspension.
摘要:
Toughened thermoplastics are prepared by mixing a water-moist elastomer component A containing up to 60% by weight of residual water with a thermoplastic polymer B and further polymers C and additives D in an extruder with mechanical dewatering of the elastomer component A, by a process in which the components A, B, C and D are fed to a twin-screw extruder which has corotating screws and essentially comprises, in the transport direction, at least one metering section in which the elastomer component A is fed to the extruder by a metering means, at least one squeeze section which serves for dewatering the component A and contains at least one retarding element and in each case at least one associated dewatering orifice, at least one section in which the thermoplastic polymer B is introduced as a melt into the extruder, at least one section provided with mixing, kneading or other plasticating elements or combinations of these elements, at least one devolatilization section which is provided with at least one devolatilization orifice and in which the residual water is removed as steam, and a discharge zone, the water emerging from the dewatering orifices being present partially or completely in the liquid phase, and the components C or D or mixtures thereof, together or separately from one another, being fed to one or more of the stated extruder sections, either together with the component A or B or mixtures thereof or separately from A and B.
摘要:
A thermoplastic molding composition having little intrinsic color is produced from a graft copolymer and a thermoplastic polymer. The graft copolymer is produced from a soft elastomeric particulate graft base obtained by polymerization of a conjugated diene alone or with a small amount of a monoethylenically unsaturated monomer, upon which is grafted a vinylaromatic monomer and acrylonitrile and optionally another monoethylenically unsaturated monomer. The thermoplastic polymer is a copolymer of a vinylaromatic monomer and acrylonitrile and optionally an additional monoethylenically unsaturated monomer. The thermoplastic molding composition has a low level of intrinsic color coupled with good mechanical properties and can be processed by, for example, extrusion, injection molding, calendaring, blow molding, compression molding, or sintering.