Patent GB-735030-A (GB)
Title: Processes for preparing new organo-tin compounds and plastic compositions
Inventor: MACK GERRY P
IPC: C08K5/57
Filed: 1952-05-06
Abstract: Resinous compositions include as a major constituent a halogen-containing synthetic resin and as a stabilizer an organo-tin compound having a tetravalent tin atom linked to 2 or 3 alkyl or aryl radicals and the remaining tin valences linked to organic radicals of which the carbon atom directly linked to the tin atom is further linked to 2 or 3 methylene activating groups (see Group IV (b)).  The preferred organo-tin compounds are of the general formula <FORM:0735030/IV (a)/1> wherein R represents an alkyl or aryl radical, R1 represents hydrogen or an alkyl, aralkyl or aryl radical or a methylene activating group, R2 and R3 are the same or different methylene activating groups, and n is 2 or 3.  Suitable methylene activating groups are the carboxyl, carbonyl, nitrile, sulphone, nitro and nitrosyl groups, and groups containing ethylenic double bonds, triple bonds, aliphatic conjugated double bonds and conjugated double bonds in aromatic rings.  The composition may contain one or more of any of the following resins:-polymers of vinyl chloride and copolymers thereof with vinyl esters of aliphatic acids, particularly vinyl acetate, copolymers of vinyl chloride with esters of acrylic and methacrylic acids, and acrylonitrile, copolymers of vinyl chloride with diene compounds and unsaturated dicarboxylic acids and their anhydrides such as copolymers of vinyl chloride with diethyl maleate, diethyl fumarate and maleic anhydride, after chlorinated polymers and copolymers of vinyl chloride, copolymers of vinyl chloride and vinylidene chloride with unsaturated aldehydes and ketones such as acrolein, crotonaldehyde and vinyl methyl ketone, vinyl methyl ether and vinyl isobutyl ether, polymers of vinylidene chloride and copolymers thereof with vinyl chloride, polymers of vinyl chloroacetate and dichlordivinyl ether, chlorinated polymers of vinyl acetate, chlorinated polymeric esters of acrylic acid and alpha-substituted acrylic acids, polymers of chlorinated styrenes such as dichlorostyrene, chlorinated rubber, rubber hydrochloride, chlorinated rubber hydrochloride, chlorinated polymers of ethylene, and polymers and after-chlorinated polymers of chlorobutadienes and their copolymers with vinyl chloride, and the corresponding bromides and fluorides.  The organo-tin compounds may be added before, during or after polymerization of the halogen-containing compound.  A suitable quantity of the organo-tin compound is from 0.1 to 5 per cent of tin by weight of the halogen-containing synthetic resin.  In the examples a composition containing a vinyl chloride-vinyl acetate copolymer and di-(2-ethylhexyl) phthalate is stabilized with the organo-tin compound <FORM:0735030/IV (a)/2> and with the organo-tin compound <FORM:0735030/IV (a)/3> a composition containing a vinyl chloride resin and di-(2-ethylhexyl) phthalate is stabilized with the organo-tin compound <FORM:0735030/IV (a)/4> a composition containing a vinyl chloride-maleic ester copolymer and dioctylphthalate is stabilized with the organo-tin compound <FORM:0735030/IV (a)/5> and a composition containing a vinyl chloride-vinylidene chloride copolymer and di-(2-ethylhexyl) phthalate is stabilized with the organo-tin compound <FORM:0735030/IV (a)/6>ALSO:The invention comprises organo-tin compounds wherein a tetravalent tin atom is linked to 2 or 3 alkyl or aryl radicals and the remaining tin valences are linked to organic radicals of which the carbon atom directly linked to the tin atom is further linked to 2 or 3 methylene activating groups, and the preparation thereof by reacting in an anhydrous organic solvent in the presence of an alkaline condensing agent the required organo-tin halide with an organic compound having a methylene group activated by 2 or 3 methylene activating groups.  Suitable methylene activating groups referred to are the carboxyl, carbonyl, nitrile, sulphone, nitro, and nitrosyl radicals, ethylenic double bonds, aliphatic conjugated double bonds, triple bonds, and conjugated double bonds in aromatic rings.  The organo-tin compounds may be of the general formula <FORM:0735030/IV (b)/1> wherein R represents an alkyl or aryl radical, R1 represents hydrogen or an alkyl, aralkyl or aryl radical or a methylene activating group, R2 and R3 are the same or different methylene activating groups, and n is 2 or 3.  The above process is preferably carried out in an inert anhydrous solvent, e.g. an aromatic hydrocarbon such as benzene, toluene or xylene, or anhydrous alcohols or ethers.  The above process may be modified in that an alkali metal derivative of the compound containing the active methylene group may be reacted with the organo-tin halide. Suitable methylene activating groups are the carboxyl, carbonyl, nitrile, sulphone, nitro, nitrosyl, ethylenic double bond, aliphatic conjugated double bond and triple bond groups and groups containing conjugated double bonds in atomatic rings.  Suitable organo-tin halides for the reaction are dimethyl, diethyl, dipropyl, dibutyl, diamyl, dihexyl, dioctyl, dilauryl, dibenzyl, diphenyl and ditolyl dichlorides and dibromides as well as the corresponding trialkyl and triaryl halides.  Reactants containing a methylene group activated by two similar methylene activating groups include malonic esters, beta-diketones and disulphones, and reactants containing different methylene activating radicals include keto-sulphones, beta-keto-carboxylic acid derivatives, aryl benzyl cyanides, aryl alkyl ketones, aryl acetic acids and cyanoacetic esters.  The reactants containing the active methylene group may have the methylene group attached to aromatic or bicyclic double bond systems, e.g. as in cyclopentadiene, indene, fluorene or triphenylmethane. When malonic esters are used, e.g. the di-methyl, ethyl, propyl, butyl, 2-ethylhexyl, benzyl, cyclohexyl or tetrahydrofurfuryl malonate, the organo-tin products are of the general formul R2Sn(CR1(COOR11)2)2\t and R3SnCR1(COOR11)2, wherein R represents an alkyl or aryl radical, R1 represents hydrogen or an alkyl or aralkyl radical and R11 represents the residue of an aliphatic, aromatic or alicyclic alcohol.  Similar organo-tin compounds can be prepared using malonic amides and nitriles. Other malonic ester type compounds may be used also, e.g. the compounds obtained by reacting any of the malonic esters referred to above with an aldehyde such as formaldehyde, acetaldehyde, butyraldehyde or benzaldehyde in the presence of a secondary amine such as piperidine or diethylamine and having the formula <FORM:0735030/IV (b)/2> wherein R1 is the alkylene or arylene residue from the aldehyde used in the condensation, or hydrogen if formaldehyde is used and R11 has the above significance, e.g. when such a compound is reacted with an organo-tin dihalide the products are of the general formula <FORM:0735030/IV (b)/3> wherein R represents an alkyl or aryl radical and R1 and R11 have the above significance.  Similar malonic ester type reactants are obtained by condensing malonic esters with unsaturated compounds having activated double bonds such as methyl vinyl ketone, ethyl acrylate and acrylonitrile.  b -diketo compounds wherein the methylene group is activated by two neighbouring carbonyl groups form compounds of the general formul  R2Sn[CR1(COR11)2]2 and R3SnCR1(COR11)2 wherein R and R11 represent alkyl or aryl radicals and R1 represents hydrogen or an alkyl or aralkyl radical.  A number of suitable b -diketones are referred to.  A further group of compounds containing an activated methylene group are the b -ketocarboxylic derivatives of the general formula R11COCHR1Z wherein R11 represents an aryl or alkyl radical, R1 represents hydrogen or an alkyl or aralkyl group and Z represents an ester, amide or nitrile group.  A number of such reactants are specified and form compounds of the general formul  <FORM:0735030/IV (b)/4> and <FORM:0735030/IV (b)/5> wherein Z, R, R1 and R11 have the above significance. When the activated methylene group lies between a sulphone group and another methylene activating group, the organotin compounds may be of the general formula <FORM:0735030/IV (b)/6> wherein R and R11 are the same or different alkyl or aryl radicals, R1 represents hydrogen or an alkyl or aralkyl radical, X is a methylene activating group such as SO2R11, COR11, COOR11 (R11 being an alkyl or aryl radical), CONH2 or CN, and n and m are each 2 or n is 3 and m is 1.  A number of suitable sulphone reactants are referred to.  Reactants containing three methylene activating groups have the general formula <FORM:0735030/IV (b)/7> wherein R1, R11 and R111 may be the same o different and may be any of the groups COR, COOR (R being an alkyl or aryl radical), CONH2 and CN.  The radicals R1 and/or R11 may also be groups containing olefinic double bonds or conjugated double bonds of the benzene nucleus, or the group SO2R where R is an alkyl or aryl radical, R111 being any of the groups referred to above.  A number of such reactants are specified.  In the examples organo-tin compounds are prepared by reacting di-butyl tin dichloride with diethyl malonate, dibutyl malonate, di 2-ethylhexyl malonate, benzyl diethyl malonate, methylene bis diethyl malonate, acetylacetone, 3-(2-ethylhexyl) pentanedione-2,4, 3-benzyl pentanedione-2,4, butylacetoacetate, ethylacetoacetate, ethylbenzoylacetate, ethyl butylacetoacetate, methyl cyanoacetate, p-phenylsulphonyl-acetone and ethyl diacetyl acetate, and by reacting tributylin chloride with dibutyl malonate, ethyl diethylmalonate, acetylacetone, methyl amyl acetoacetate and indene.ALSO:Organo-tin compounds of the formul  <FORM:0735030/III/1> and <FORM:0735030/III/2> wherein R represents an alkyl or aryl radical, R1 is hydrogen or an alkyl or aralkyl radical and R11 represents an amyl or higher radical, are soluble in mineral oils.ALSO:Chlorinated rubber, rubber hydrochloride and chlorinated rubber hydrochloride and