Patent GB-799043-A (GB)
Title: Improvement in vinylic fillers and the reinforcement of elastic and plastic materials therewith
IPC: C08L21/02
Filed: 1954-08-27
Abstract: Latices, or other colloidal dispersions of rubber or of synthetic elastomers or of plastomers, are mixed with a latex or colloidal dispersion of vinylic filler resin which has been cross-linked to a state of substantially complete insolubility in organic solvents generally and which acts as an insoluble reinforcing filler in the final composition obtained by their co-coagulation.  The filler particles are insoluble in the compound and are therein distributed as particles of colloidal size.  Such filler resins are the homo- or multi-polymerization products of monomers containing one or more polymerizable unsaturated linkages, i.e. vinyl, allyl, polyvinyl, polyallyl or vinyl-allyl monomers which, such as divinyl benzene, are cross-linked in themselves to a state of insolubility or, not being cross-linking, are so cross-linked by such agents as divinyl benzene, ethyleneglycoldimethylacrylate, N.N.-methylenebisacrylamide, triallylcyanurate, N.N-diallylmelamine, allylacrylate and allyl methacrylate.  The vinylic fillers may be of non-polar type, or of polar type containing groups such as carboxyl, hydroxyl, halogen, amino, nitrile, acid amide, aldehyde or carbonyl.  Those having residual unsaturation may have chlorine or bromine addition.  The filler latex may be made with or without an emulsifying agent.  The insolubility of the filler in the material to be reinforced may be determined by observing any change in viscosity of the latex when suspended in a solvent such as dioxane or by observation by an electron microscope of the final dispersion of the filler in the material.  The filler may be a graft-interpolymer such as by emulsion-polymerizing styrene with a crosslinking agent and then, in another polymerization step, coating with a monomer such as ethylene glycoldimethylacrylate or allylacrylate; and further coatings may be provided.  Where actual bonding of the filler to the material is desired, a chemically active coating may be provided such as by coating with acrolein, methacrolein or crotonaldehyde when the material to be reinforced is a phenol formaldehyde or other aldehyde condensation polymer, or with vinyl ethers or polyhydroxy compounds such as glycerol vinyl ether, or polymerizable acids such as acrylic or methacrylic acids to provide hydroxyl or carboxyl groups on the vinylic filler for attachment to other polyfunctional acids or alcohols or amines or isocyanates in the material.  The material to be reinforced may be (1) natural rubber or balata; chicle or interpolymers of natural rubber and dienes, vinyls and allyl monomers; or their chemical derivatives such as hydrogenated, hydroxylated, chlorinated or hydrochlorinated materials; (2)(a) synthetic vulcanizable elastomers comprising non-polar dienic homopolymers such as isoprene, piperylene, 1.3-pentadiene, dimethyl butadiene, or multipolymers of such dienes with or without vinyl compounds and other non-polar materials containing a polymerizable ethylenic group such as of isopreneisobutylene and including the GR-S type of butadiene-styrene copolymer (high butadiene content) even when including a small proportion of cross-linking agent to reduce polymer shrinkage; (b) synthetic vulcanizable elastomers comprising polar dienic homopolymers such as polychloroprene (Neoprene) or multipolymers such as butadiene-acrylonitrile copolymers; (c) synthetic vulcanizable elastomers comprising non-dienic polymers such as polyalkylene sulphide ("Thiokol" (Registered Trade Mark)); lactoprene polymers not including dienic components and using an ester exchange or halogen replacement reaction for vulcanization; elastoplastics such as vulcanizable mixed glyptals; polyesters containing residual unsaturation and curable by organic peroxide; polyesters vulcanized through terminal carboxyl or hydroxyl groups, e.g. by reaction with a polyisocyanate to form elastomers of the Vulcollan type; (3) non-vulcanizable elastomers and plastomers both thermoplastic and thermosetting, such as polyvinyl chloride and polyvinylidene chloride, isobutylene-styrene copolymers, polysulphones; polymers from halogenated vinyl compounds such as chlorostyrene; from vinyl acids and esters such as methylmethacrylate; from vinyl ethers, alcohols and esters such as vinyl butyrate; from nitrogen containing vinyl monomers such as vinyl pyridine or acrylonitrile; or "Bakelite" (Registered Trade Mark) and other thermosetting plastics or cellulose esters or ethers.  The Specification contains 29 tables setting out various examples of mixes and the properties of the resultant reinforced material.  Table III gives examples of quantities of monomer, water, emulsifier, catalyst and modifier used in producing filler latices and which are referred to in the other tables showing the use of specific fillers; Table XII gives examples of quantities of vulcanizing chemicals and adjuvants for similar reference.  In the remaining tables details are given of the results of mixing latices of material to be reinforced and of cross-linked reinforcing vinylic filler.  Table I-GRS (butadiene-styrene) is mixed with a cross-linked filler derived from divinyl benzene or ethylene-glycoldimethacrylate alone or various combinations of styrene methacrylic acid, vinyl toluene, isoprene and o-chlorostyrene, using divinyl benzene or ethyleneglycoldimethacrylate as cross linking agent: Table II-GRS and filler from styrene, or styrene and methacrylic acid or butadiene or styrene, vinylpyridine and methylmethacrylate using divinyl benzene and alpha - isopropylaminopropionitrile as compounding adjuvant. Table IV natural rubber mixed with filler from styrene cross-linked by divinyl benzene and acrylonitrile cross-linked by ethyleneglycoldimethylacrylate and compared with a rubber-soluble non-crossed-link styrene resin; Tables V and VI polybutadiene or GRS with filler from styrene cross-linked by divinyl benzene and methylmethacrylate crosslinked by ethylene glycoldimethylacrylate compared with elastomer-soluble non-cross-linked styrene resin; Table VI-A-butyl rubber (isopreneisobutylene copolymer) with filler from styrene cross-linked by divinyl benzene; Table VII polychloroprene with filler from styrene or o-chlorostyrene cross-linked by divinylbenzene; Table VIII butadiene-acrylonitrile copolymer with filler from methyl methacrylate, vinyl pyridine, styrene or from o-chlorostyrene crosslinked by divinyl benzene; Table IX polyalkylene sulphide ("Thiokol" (Registered Trade Mark)) with filler from acrylic acid and styrene cross-linked by divinyl benzene; Table X vinylchloride - vinylidene chloride copolymer with filler from styrene or from methyl methacrylate cross-linked by divinyl benzene; Table XI polyvinyl acetate or polyvinyl butyral or styrene-acrylonitrile or ethyl cellulose with filler from styrene polymerized with methacrylic acid using divinyl benzene as cross-linking agent; Table XIII interpolymers of polybutadiene and styrene or polychloroprene and methyl methacrylate with filler from methyl methacrylate, methacrylic acid and butadiene cross-linked by ethylene glycoldimethylacrylate; or an interpolymer of natural rubber and methyl methacrylate with filler from methyl methacrylate and methacrylic acid, cross linked by ethylene glycoldimethylacrylate allyl amine being used as a compounding adjuvant with the rubber and polybutadiene mixes; Table XIV mixed elastomers of polybutadiene and butadiene-styrene copolymer or butadiene-styrene copolymer and butadieneacrylonitrile copolymer and filler from methyl methacrylate cross-linked by ethylene glycoldimethylacrylate; Table XV GRS admixed with an elastomer-soluble styrene-butadiene resin of low butadiene content and a filler from styrene cross-linked by divinyl benzene.  A master batch of the filler latex and one of the elastomer latices may be made and after coagulation and drying may be milled into the other elastomer; Table XVI natural rubber or polybutadiene or GRS or polychloroprene or butadiene-acrylonitrile or plasticized vinyl chloride-vinylidene chloride copolymers and filler from various combinations of acrylic acid, methacrylic acid, styrene isoprene and butadiene, cross-linked by divinyl benzene and using allylamine as compounding adjuvant with all except the chloride polymer; Table XVII GRS and filler from styrene, acrylic acid and isoprene cross-linked by divinyl benzene and with ammonia or one of the following as compounding adjuvant: allylamine, n-propylamine, di-n-propylamine, isopropylamine, di - isopropylamine, diallylamine, tri - N - butylamine, trimethylbenzyl ammonium hydroxide, N-isopropylglucamine; Tables XVIII and XIX-GRS and filler from styrene and methacrylic acid cross-linked by divinyl benzene and using 1,2-hydro - 2,2,4 - trimethylquinoline or phenyl-betanaphthylamine and alphaisopropylaminopropionitrile (Amitrile I.P.) as compounding adjuvants; Table XX a natural rubber and a polar filler from acrylonitrile or methylmethacrylate using divinyl benzene or ethyleneglycoldimethylacrylate or allyl acrylate as cross-linking agent; Table XXI-GRS and filler from a two-step interpolymerization; step I cross-linked styrene, step II styrene and methacrylic acid or vinyl toluene with ethyleneglycoldimethacrylate, divinyl - benzene, allylacrylate, or triallylcyanurate as cross-linking agents or ethylene glycoldimethyl acrylate alone: and when styrene and methacrylic acid is employed, using Amitrile I.P. as compounding adjuvant; Table XXIA-GRS with filler from an interpolymer of natural rubber or GRS or polybutadiene or dichloroprene or butadiene-acrylonitrile with filler of styrenemethacrylic acid cross-linked by divinylbenzene using alphaisopropylaminopropionitrile as compounding adjuvant; Table XXII-natural rubber or polychloropene or GRS with an emulsifier-free filler from styrene with or without methacrylic acid or N - tert. - butylacrylamide, and using N.N. - diallylmelamine or divinylbenzene as cross-l