Abstract:
Bifunctional compounds are characterized in that they have the following general formula: ##STR1## where n is zero or a whole number in the range 1 to 4, limits included, X is a substituent where the X groups are identical or different when n is a number from 2 to 4, and R is a divalent group.Use of these compounds as functionalising agents for a polyolefin by grafting the compound onto the paraffinic chain, or as compatibilising agents for incompatible polymers.
Abstract:
A polymer composition comprises at least one thermoplastic polymer selected from the group formed by polyetherimides and polysulphones and at least one epoxy resin modified by at least one aromatic polyamine. The epoxy resin is formed from at least one polyepoxide containing at least 2 epoxy groups in its molecule and the aromatic polyamine contains at least two primary amine groups in its molecule and preferably at least one alkyl substituent containing 1 to 12 carbon atoms located alpha to one of the amino groups. The molar ratio of the polyamine to the epoxy is such that, each amino group corresponds to 1.6 to 2.6 epoxy groups. The thermoplastic polymer content is preferably about 15% to 98% by weight with respect to the total weight of the polymer composition; the amount of epoxy resin modified by at least one aromatic polyamine is about 2% to 85% by weight with respect to the total weight of the polymer composition. These polymer compositions can be prepared in the molten state, without a solvent, at a temperature of about 100° C. to 250° C.
Abstract:
This invention relates to the field of processes for membrane separation and applies in particular to the purification of C2 or C3 olefins. This process makes it possible more particularly to separate propylene from a mixture that contains other C3 hydrocarbons such as propane. The membranes that are used in the process according to this invention are vitreous polymer-based membranes whose pattern contains a bis-phenyl-9,9-fluorene group.
Abstract:
This invention relates to the field of processes for membrane separation and applies in particular to the purification of C2 or C3 olefins. This process makes it possible more particularly to separate propylene from a mixture that contains other C3 hydrocarbons such as propane. The membranes that are used in the process according to this invention are vitreous polymer-based membranes whose pattern contains a bis-phenyl-9,9-fluorene group.
Abstract:
The invention relates to a process for membrane separation that makes it possible to separate linear hydrocarbons from branched hydrocarbons. The membrane that is used comprises a dense selective layer that consists of a polymer whose chemical structure contains at least one bis-phenyl-9,9-fluorene group.
Abstract:
A polymer composition comprises at least one thermoplastic polymer selected from the group formed by polyetherimides and polysulphones, at least one epoxy resin modified by at least one aromatic polyamine, and at least one other thermoplastic selected from the group consisting of a polyphenylene ether, a polyphenylene sulfide and an aromatic polyether. The epoxy resin is formed from at least one polyepoxide containing at least 2 epoxy groups in its molecule and the aromatic polyamine contains at least two primary amine groups in its molecule and preferably at least one alkyl substituent containing 1 to 12 carbon atoms located alpha to one of the amino groups. The molar ratio of the polyamine to the epoxy is such that, each amino group corresponds to 1.6 to 2.6 epoxy groups. The thermoplastic polymer content is preferably about 15% to 98% by weight with respect to the total weight of the polymer composition; the amount of epoxy resin modified by at least one aromatic polyamine is about 2% to 85% by weight with respect to the total weight of the polymer composition.
Abstract:
The invention relates to a process for membrane separation that makes it possible to separate linear hydrocarbons from branched hydrocarbons. The membrane that is used comprises a dense selective layer that consists of a polymer whose chemical structure contains at least one bis-phenyl-9,9-fluorene group.
Abstract:
The invention concerns a structure comprising at least one metallic surface which undergoes cathodic protection and a protective coating for said surface, said coating comprising a polymer including micro-capsules containing compounds sensitive to the electric field generated by the cathodic protection and capable of reacting in an alkaline medium to form a protective layer on the surface of the structure when it is in direct contact with a corrosive medium.The invention also concerns the coating associated with said structure.
Abstract:
The invention concerns a structure comprising at least one metallic surface which undergoes cathodic protection and a protective coating for said surface, said coating comprising a polymer including micro-capsules containing compounds sensitive to the electric field generated by the cathodic protection and capable of reacting in an alkaline medium to form a protective layer on the surface of the structure when it is in direct contact with a corrosive medium. The invention also concerns the coating associated with said structure.
Abstract:
Graft stereoblock polymers are described which contain at least one polyolefin or polydiene type sequence comprising at least one succinimide ring substituted on the nitrogen atom by a reactive group with formula —R(—X)n, where —X represents a reactive group, n is a number greater than or equal to 1 and —R is a residue containing at least one carbon atom, and containing at least one sequence of a variety of natures, different from a polyolefin or polydiene. Their preparations and uses are also described. Mixtures of polymers comprising at least two polymers which are different from each other, at least one of which is a graft stereoblock polymer as defined above, and their uses, are also described.