Patent GB-862430-A (GB)
Title: Organotin compounds containing epoxy groups and a process for their manufacture
Inventor: MACK GERRY PROTEUS
IPC: C07F7/22
Filed: 1957-07-19
Abstract: Halogen containing synthetic resins, rubber hydrochloride and chlorinated rubber hydrochloride may be stabilized against deterioration by light and heat by organotin compounds containing at least one epoxy group in the molecule and free from ­Sn-OOC- groupings.  Synthetic resins specified include polymers of vinyl chloride, vinyl chloride copolymerized with (a) vinyl esters of aliphatic carboxylic acids, (b) esters, nitriles and amides of unsaturated carboxylic acids, (c) dienes and unsaturated dicarboxylic acids, esters and acid anhydrides; after-chlorinated polymers and copolymers of vinyl chloride; polymers and copolymers of vinylidene chloride; polymers of vinyl chloroacetate and dichlorodivinyl ether; chlorinated polymers of vinyl acetate; chlorinated polymeric esters of acrylic and a -substituted acrylic acids; polymers of chlorinated styrene; chlorinated polymers of ethylene; and polymers and after-chlorinated polymers of chlorobutadienes and their copolymers with vinyl chloride.  The corresponding bromides and fluorides may also be stabilized.  Plasticizers, e.g. esters of phthalic, adipic, sebacic, azelaic, citric, aconitic, tricarballylic, maleic, fumaric, succinic, malonic, phosphoric and mercapto acids, esters of dihydric and polyhydric alcohols, and of thioglycols, amino alcohol derivatives, esteramides, sulphonamides, chlorinated plasticizers and carbonic acid derivatives derived from phosgene may also be present in the compositions.  Condensation polymers.-Organotin compounds containing at least one epoxy group in the molecule and free from ­Sn-O.CO-groupings may be polymerized by opening the oxirane ring. No examples are given, but a large number of organotin epoxy compounds are discussed, e.g. mono- and poly-epoxides containing S, N, O, OH, Br, ester groups, Cl and combinations thereof.  Further the organotin epoxy compounds of the invention may themselves be polymeric: again no examples are given but the following two types of polymers are discussed: (i) alkyd polymers containing Sn atoms in the polymer chain or network, the Sn atoms being joined to O atoms in the alkyd chain.  These Sn-containing alkyds may be prepared (a) by reacting an organotin compound, e.g. an alkyl or aralkyl tin oxide, with an alkyd; or (b) by including an organotin compound in the alkyd-forming polyhydric alcohol/polycarboxylic acid.  The epoxy groups are provided either by being already present in the components of the alkyd resin or by epoxidizing unsaturated groups in the alkyd. (ii) Polymeric Sn compounds containing a plurality of R2SnO groups linked to each other through O.  They may be prepared either by reacting an organotin dihalide with an epoxy containing alkoxide or by reacting organotin oxide with an epoxy containing ester.  A list of suitable starting materials is given.  The polymers (i) or (ii) may be used as stabilizers for the addition polymers described in the earlier part of the Specification.ALSO:The invention comprises organotin compounds containing at least one epoxy group in its molecule and free from ­Sn-OOC-groupings.  The compound may have that portion containing the epoxy group linked to the tin atom by an oxygen atom viz: Ra111SN(OR)4-a by a sulphur atom: Ra111Sn(SR)4-a by a nitrogen atom: Ra111Sn(-N1-R)4-a or it may be an epoxy-containing hydrocarbon group RxSnR1114-x where a is 0, 1, 2 or 3, x is 1, 2, 3, or 4, R is an organic epoxy containing group and R111 is a substituted or unsubstituted aliphatic, cycloaliphatic, aromatic or heterocyclic group, which, if substituted, contains no substituents reactive with the other constituents of the organotin molecule and which do not interfere with the action of the epoxy group when in service.  The invention also includes compounds containing more than one of the groups above e.g.  <FORM:0862430/IV (b)/1> R3Sn-O-Sn-R3 &c. (where R1 is as defined for R111 above).  The organic group may be epoxidised before or after reaction with an organotin compound. When the organotin reactant is a halide (e.g. reacting an epoxyalcohol with dioctyl tin dichloride) a hydrogen halide absorbing material should be present.  Many examples are given in the Specification.  The compounds of the invention may be used as stabilisers for halogen containing synthetic resins (see Group IV(a)).