Dupont Canada Inc.

E.i. Dupont De Nemours and Company

Chun Sing Wong

Herbert Vernon Bendler

Hari Babu Sunkara

Howard C Ng

David J Walsh

Howard Chung-Ho Ng

Ronald A Zelonka

A curable thermoplastic elastomeric blend comprising: (a) from 15 to 60 weight percent of a polyalkylene phthalate polyester polymer or copolymer and; (b) from 40 to 85 weight percent of a poly(meth)acrylate or polyethylene/alkyl (meth)acrylate rubber in combination with an effective amount of peroxide free-radical initiator and an organic multiolefinic coagent to cross-link which upon extrusion or injection molding dynamically cross-link producing a melt processible thermoplastic elastomeric composition having a polyalkylene phthalate polyester polymer or copolymer continuous phase and of a cross-linked polyacrylate or polyethylene/acrylate rubber dispersed phase. Such compositions are useful in the manufacture of rubber parts having excellent resistance to lubricating oils and greases.

Curable thermoplastic elastomeric blend, method of manufacture, and use thereof

The present invention relates to a curable thermoplastic elastomeric composition based on a polytrimethylene ether ester elastomer and a crosslinkable poly(meth)acrylate rubber system; and a melt processible thermoplastic elastomeric compositions based on a continuous phase comprising of a polytrimethylene ether ester elastomer and a disperse phase of a crosslinked poly(meth)acrylate rubber. A process for manufacturing such a melt processible thermoplastic elastomeric composition, and a shaped article (e.g. an extruded or molded article) made thereform, are also disclosed.

Thermoplastic elastomer blend, method of manufacture and use thereof

A curable thermoplastic elastomeric blend comprising: (a) from 15 to 60 weight percent of a polyalkylene phthalate polyester polymer or copolymer and; (b) from 40 to 85 weight percent of a polyacrylate or polyethylene/acrylate rubber in combination with an effective amount of peroxide free-radical initiator and an organic diene co-agent to cross-link which upon extrusion or injection molding dynamically cross-link producing a melt processible thermoplastic elastomeric composition having a polyalkylene phthalate polyester polymer or copolymer continuous phase and of a cross-linked polyacrylate or polyethylene/acrylate rubber disperse phase. Such compositions are useful in the manufacture of rubber parts having excellent resistance to lubricating oils and greases.

The present invention relates to coated metal substrates such as metal piping having improved environmental stress crack resistance and resistance to hydrolytic and/or cathodic disbondment. The coating composition contains a blend of modified and unmodified polyolefins as well as a tackifier. For cathodic disbondment resistance, the preferred tackifiers are rosin esters or hydrogenated versions thereof. The modified polyolefins are grafted versions of metallocene or non-metallocene produced low density or high density polyethylenes.

Moisture resistant coated metal substrates

There is provided a process for improving the color of anhydride-grafted polymers. The process includes the steps of admixing in an extruder a polyolefin, a free radical initiator, and an anhydride-providing monomer at a temperature above the melting point of the polyolefin, adding an effective amount of an oxo-boron compound to the admixture; and extruding the resultant anhydride-grafted polymer into a shaped article.

Process for preparing anhydride-grafted polymers with improved color

The present invention relates to polymeric co-grafting of massing polymers and copolymers of ethylene and one or more &agr;-olefins having at least 4 carbon atoms. The co-grafts are useful tougheners for polyamides.

Non-massing tougheners for polyamides

A coextrudable adhesive composition formed from a polymer component and a catalytic agent is disclosed. The polymer component is selected from grafted polymers formed by grafting polyolefins with an ethylenically unsaturated carboxylic acid or anhydride. The catalytic agent is a monoalkyl phosphate, alkylamine, heterocyclic compound or aminocarboxylic acid. The compositions show improved adhesion to polar substrates compared with the related compositions that do not contain the catalytic agent. The compositions may be used, for example, in the bonding of ethylene/vinyl alcohol polymers to polyolefins and polyamides.

Coextrudable adhesives

Corrosion of metals and cathodic disbondment of coated metals, especially steel, iron and aluminum, are reduced by coating the metals with a composition of 1-70% by weight of a modified polyolefin and 30-99% by weight of metallic zinc. The modified polyolefin is obtained by grafting a polyolefin with an ethylenically unsaturated aliphatic carboxylic acid or derivative thereof, the polyolefin being a homopolymer or copolymer of a C.sub.2 -C.sub.12 hydrocarbon alpha-olefin.

Reduction of corrosion of metals

A method for the grafting of at least two different monomers onto molten hydrocarbon polymer, in which the monomers are capable of undergoing thermally induced copolymerization, is disclosed. The method involves contacting one of said monomers with the other of said monomers in the presence of molten polymer and under admixing conditions such that the monomers and polymer are rapidly admixed. In preferred embodiments, the process is operated in the absence of initiator for the grafting reaction and in the substantial absence of antioxidant in the polymer. Preferably, one of the grafting monomers is selected from the group consisting of styrene, 2-methyl styrene, 4-methyl styrene, alpha-methyl styrene, beta-methyl styrene, 4-vinyl anisole, stilbene and indene, and mixtures thereof, and the other of the grafting monomers is selected from the group consisting of maleic anhydride, itaconic anhdride, citraconic anhydride, maleimide and N-phenylmaleimide, and mixtures thereof. In emobodiments, the polymer is a homopolymer of ethylene, propylene or 4-methyl pentene-1, or a copolymer of ethylene and/or propylene with at least one of butene-1, hexene-1, 4-methyl pentene-1 and octene-1. The grafted polymers may be used in coatings, adhesives or the like, or in the form of film, moulded articles or the like.

Method for grafting monomers onto molten hydrocarbon polymer

A continuous process for the grafting of ethylenically unsaturated monomers onto homopolymers of ethylene and copolymers of ethylene and C.sub.4 -C.sub.10 higher alpha-olefins is disclosed. The process involves feeding to an extruder an admixture comprising (i) a major portion of the above polymer of ethylene, (ii) the monomer, (iii) 25-500 ppm of an organic peroxide and (iv) a minor portion of a normally solid thermoplastic polymer having a melting point of less than 185.degree. C. and a shear viscosity at 200.degree. C. and a shear rate of 400 sec.sup.-1 that is not more than 50% of that of the polymer of ethylene. The organic peroxide is in the form of a composition with the thermoplastic polymer. The admixture is mixed in a first zone at a temperature above the melting point of the polymers for at least ten seconds but for less than 25% decomposition of the peroxide and then in a second zone for a period that is at least four times the half-life of the peroxide. A grafted polymer having a melt index that is 20-100% of that of the polymer prior to grafting is obtained. The grafted polymer may be used in a variety of end-uses, for example, the manufacture of film, moulding of articles, extrusion coating of metals and coextrusion processes.

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Kingston, Canada

Chun Sing Wong