摘要:
These compositions based on semi-crystalline thermoplastic resin and on ABC block copolymers result in materials or in items which exhibit an impact strength, an elongation at break, a resistance to cracking and to deformation under stress, and a thermal behavior which are improved with respect to semi-crystalline resin or resins alone or mixed with conventional impact additives, while retaining a high modulus and thus a degree of stiffness. They are generally suitable for the preparation of items or articles, such as sheets, films, pipe sheathings, tubings, pipes, yarns, strands, cable sheathings, bracing wires, leaktight sheathings, sleeve tubes, both mono- and multilayer, shaped components, molded panels, thermoformed articles, sections, bottles or powders for coating substrates. The materials or items obtained from these compositions exhibit a characteristic morphology visible in electron microscopy.
摘要:
The invention relates to a shock-reinforced thermoplastic composition comprising at least one polyamide and at least one block copolymer having a block that is entirely or mainly comprised of sydiotactic methyl polymethacrylate at a rate of more than 60%. The inventive composition has excellent mechanical properties and can be used in various applications.
摘要:
Use is made, for selectively hydrogenating the olefinic double bonds of block copolymers, at least one block of which comprises olefinic double bonds, using a catalyst based on a metal from Group VIII in a medium comprising an organic solvent for the copolymer and an ionic liquid as solvent for the catalyst, of a water-immiscible ionic liquid, preferably an ionic liquid for which the anion is the hexafluorophosphate anion and the cation is the 1-butyl-3-methylimidazolium (bmim+) or 1-ethyl-3-methylimidazolium (emim+) cation.Applied to poly(styrene)-b-poly(butadiene)-b-poly(methyl methacrylate) block copolymers, the poly(butadiene) block of which predominantly possesses a 1,4-microstructure, this process results in copolymers for which the degree of hydrogenation is at least equal to 50% and which exhibit a melting point of greater than 30 °C.
摘要:
The present invention relates to a process for producing impact modifiers, impact modified thermoplastic molding compositions and in particular impact modified polycarbonate or polycarbonate/polyester blends having improved resistance to degradation. More particularly the present invention relates to a process for producing polymeric impact modifiers with a core-shell structure made by a multistage process comprising a control and adjustment if necessary of the pH value before and during the recovery step.
摘要:
The present invention relates to a composition containing at least one lactic acid homopolymer and at least one block copolymer with a polydispersity index ranging from 1.5 to 5 and comprising: at least one block A that is miscible with the homopolymer and formed from monomers containing at least one methacrylate of formula CH2═C(CH3)—COOR1, and at least one block B that is immiscible with the homopolymer and formed from monomers containing at least one alkyl acrylate of formula CH2═CH—COOR2 and/or at least one methacrylate of formula CH2═C(CH3)—COOR3. The invention also relates to the use of this composition for the manufacture of medical articles, textile fibers, thermoformed plates or packaging, in particular films or bottles.
摘要:
The present invention relates to a process for the preparation of a copolymer of at least one cyclic monomer chosen from a lactone, a lactam, a lactide and a glycolide, comprising the stage consisting in reacting said cyclic monomer with a polymeric initiator in the presence of a compound carrying a sulfonic acid functional group.It also relates to the polymer composition obtained according to this process and to its uses, in particular as antistatic additive.
摘要:
The invention relates to is a crosslinked composition containing in parts by weight: 20 to 100 parts of at least one elastomer (I), 2 to 50 parts of at least one core/shell copolymer (II), and 0 to 100 parts of at least one thermoplastic polymer (III). The invention also relates to a method of producing one such crosslinked composition, which is characterized in that it consists in: mixing an elastomer and a core/shell copolymer optionally in the presence of: a grafted polyolefin, a plasticizer, fillers and/or additives, and a suitably-selected crosslinking system, and subsequently crosslinking said mixture at a suitable temperature. In a preferred embodiment of the invention, the mixture is crosslinked at a temperature of between 150 and 320° C. The invention method be carried out in an internal mixer, or, alternately, in a twin-screw extruder or a Buss®-type co-kneader. Depending on the case, the resulting mass is calendared or extruded, cooled and subsequently granulated. The granules thus obtained are then ready to be transformed, by means of heating, into sheets, plates, extrusions, tubes or other desired products. The invention further relates to the use of one such composition in the production of ducts, pipes, tubing, couplers or similar for conveying fluids, such as the fluid transfer conduits, pipes and other elements which are used in the automobile industry in braking, cooling, steering and air-conditioning systems. The inventive crosslinked composition can also be used in the production of belts, tires, electrical cable sheaths, and shoe soles.”
摘要:
The invention relates to a method for continuously and dynamically mixing at least two fluids. Said method comprises the following steps: a) the rotor (1) of a micromixer is rotatably driven, said micromixer comprising a rotor (1) which is provided with a shaft (2) encompassing blades (3) that are arranged in groups (3a-3g), a stator (4) which is provided with at least one inlet (5) for a first fluid, at least one inlet (6) for a second fluid, and an outlet (7); b) the fluids are fed into the micromixer; and c) a micromixture of the fluids is collected at the outlet (7) of the micromixer. The inventive method is particularly suitable for rapid and/or complex kinetic chemical reactions such as anionic polymerization. The invention also relates to a micromixer for carrying out said method.
摘要:
The process for the continuous preparation of homopolymers or copolymers by free-impinging-jet micromixing of fluids formed (1) of monomer(s) and (2) of an initiator system consists in micromixing the said fluids (1) and (2) and in recovering the mixture of these fluids in the form of a resultant jet Jr, originating from the point of impingement (I).
摘要:
The present invention relates to thermoplastic compositions comprising as impact modifier a rubber containing graft polymer prepared by the process of emulsion polymerization and recovered by a special process controlling and adjusting the pH value, the use of the thermoplastic compositions in the production of molded bodies, and to the molded, bodies themselves. The present invention relates also to thermoplastic compositions comprising a polymeric impact modifier with a core-shell structure made by a multistage process and recovered by a special process controlling and adjusting the pH value comprising at least one gradient polymer the use of the thermoplastic compositions in the production of molded bodies, and to the molded, bodies themselves.