The Dow Chemical Company

Gerald M Lancaster

David C Kelley

Ricky L Tabor

James A Allen

Tu-Anh Pham

Chad A Strait

Kenneth L Bryce

Russell H Cramm

Charles V Neywick

Paul L Neill

Stephen M Hoenig

Zdravko P Jezic

James A Vanderhider

Luis C Mulford

Gene P Young

Michael K Laughner

Robert B Turner

Edward R Peterson

Malcolm F Finlayson

Morris S Edmondson

Yun C Sun

John O Bieser

Llewellyn D Booth

Thomas I Butler

Michael W Potts

John O Biesser

Gregory E Johnson

Jim T Herman

A method is disclosed for making thermoplastic bicomponent fibers by contacting under thermally bonding conditions (a) a first component being at least one high performance thermoplastic polymer, such as PET, PBT, nylon or the like, and (b) a second component which is olefinic and which forms at least a portion of the fiber's surface characterized by (b) including at least one grafted olefinic polymer, preferably at least one grafted linear ethylene polymer, having pendant succinic acid or succinic anhydride groups; whereby the fiber is dyeable. The bicomponent fibers made by this process can be in a variety of shapes (e.g., round, oval, trilobal, flat, or hollow) and configurations (e.g., symmetrical sheath/core or side-by-side or asymmetrical crescent/moon). The succinic acid or succinic anhydride groups are provided by grafting, respectively, maleic acid or maleic anhydride onto the linear ethylene polymers especially by a process wherein the grafting is done in a twin-screw, co-rotating extruder with the maleic acid or maleic anhydride being injected into a pressured zone of the extruder. The acid containing grafted linear ethylene polymer or polymer blends are dyeable in contradistinction to ungrafted linear ethylene polymers.

Method for making bicomponent fibers

A process is described for stabilizing the melt flow rate and melt tension of ethylene-carbon monoxide interpolymers with a hindered phenol antioxidant. The antioxidant is melt blended with the polymer before it is exposed to air.

Process for producing stabilized ethylene carbon monoxide interpolymers

Additives which have low loss factors and high dielectric constants are added to olefin/carbon monoxide copolymers, thereby synergistically enhancing the beneficial thermal response of the copolymers to the action of radio frequency energy, especially microwave energy. The additives may be, e.g., metal salts, metal oxides, and metal-organic compounds. The copolymer is preferably comprised of ethylene/carbon monoxide (E/CO) or a terpolymer of E/CO/M, where M represents minor amounts of one or more other olefinically-unsaturated monomers which are copolymerizable with ethylene.

Activation of ethylene/carbon monoxide polymers

Ethylene polymers grafted with dicarboxylic acid functionality have synergistically improved adhesive properties and acquire heatability employing RF electromagnetic radiation when blended with a carbon monoxide-containing ethylene polymer. The dicarboxylic acid grafted and carbon monoxide-containing ethylene polymers and blends thereof are particularly useful as adhesive layers in laminate structures where RF heat sealing methods can be employed.

Adhesive, RF heatable grafted polymers and blends

Multicomponent thermoplastic resin blends are disclosed which have a nonisothermal crystallization half life of less than thirty seconds. Especially preferred are three component resin blends comprising a maleic anhydride grafted HDPE, an unmodified LLDPE copolymer having a density between about 0.905 and 0.93 g/cc, and an unmodified LLDPE copolymer having a density between about 0.89 and 0.92 g/cc. These thermoplastic resin blends can be used as the adhesive layer in multilayer structures. They are especially useful in blown film multilayer structures and they show particularly good adhesion to polar substrates, e.g., EVOH substrates.

Non-isothermal crystallizable adhesive compositions for multilayer

Maleic anhydride can be satisfactorily grafted to polymers at low pressures by feeding the polymer through a multiple screw extruder and injecting the maleic anhydride and a free radical initiator into the extruder. The maleic anhydride and initiator can be pre-mixed in a solvent solution. The solvent and unreacted maleic anhydride can be removed by low pressure devolatilization. The graft copolymer has a yellowness index as measured by ASTM D-1925-70 less than about 10.0 and as measured by ASTM E-313-73 less than about 11.0. Further, between 0.75 and 2.0 weight percent of the graft copolymer comprises maleic anhydride. The graft copolymer can further be blended with an olefinic polymer to yield adhesive thermoplastics suitable for use as food packaging multilayer coextruded films.

Meleic anhydride graft copolymers having low yellowness index and films

Carbon monoxide-containing ethylene polymers are blended with vinyl alcohol polymers, including vinyl alcohol homopolymers and copolymers, to prepare oxygen barrier resins having good processability.

Oxygen barrier resins

Succinic acid or succinic anhydride grafts of linear ethylene polymers are blended with other polymers or resins, e.g. polyesters and the like, to form blends having useful adhesive properties. The adhesive properties are useful in various laminates and in bicomponent fibers which comprise a core of a performance fiber, especially a polyester such as PET or PBT and polyamides, and a sheath of the grafted LDPE, HDPE or LDPE. The succinic acid or succinic anhydride groups are provided by grafting, respectively, maleic acid or maleic anhydride onto the LDPE, LLDPE, and HDPE, especially by a process wherein the grafting is done in a twin-screw, co-rotating extruder with the maleic acid or maleic anhydride being injected into a pressured zone of the extruder. The acid containing grafted polymer is dyeable in contradistinction to ungrafted polymer.

Maleic anhydride grafts of olefin polymers

A polycarbonate blend having both improved solvent resistance and improved impact strength comprising in admixture a polycarbonate, a styrenic thermoplastic resin, a grafted olefin/carbon monoxide copolymer and, optionally, a rubber toughening agent.

Polycarbonate/styrenic blends modified with a grafted olefin copolymer

Maleic anhydride graft copolymers having low yellowness index and films

Foamed products are prepared by subjecting a crosslinked polymer such as an ethylene-carbon monoxide copolymer susceptible to heating by high frequency electromagnetic radiation such as microwave or radio frequency which has been imbibed or impregnated with a suitable mechanical or physical blowing agent such as a halogenated hydrocarbon to sufficient high frequency electromagnetic radiation to cause foaming of the polymer.

Foamable thermoplastic polymers and a method for foaming

Packaging containers which are closed, except for a pinch-type filling valve or filling-opening, are provided with an RF-sealable polymer, at least in the valve or opening, in order to be able to seal the valve or opening using RF frequency. Preferably, polymers which are sealable using MW energy are used, including, preferably, carbon monoxide-containing ethylene polymers.

Growing community of inventors

Freeport, TX, United States of America

Gerald M Lancaster