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    Process for the production of siliconcontaining trioxane copolymers
    37.
    发明授权
    Process for the production of siliconcontaining trioxane copolymers 失效
    制备含硅三氧杂环己烷共聚物的方法

    公开(公告)号：US3369039A

    公开(公告)日：1968-02-13

    申请号：US52484466

    申请日：1966-02-03

    Applicant: BAYER AG

    Inventor： DER EMDEN WOLFGANG VON ,  KUNO WAGNER ,  HANS NIEDERPRUM ,  WALTER SIMMLER

    IPC: C07F7/08 ,  C08G2/00

    CPC classification number: C08G2/06 ,  C07F7/0841 ,  C08G2/18

    Abstract: 1,142,646. Silicon-containing copolymers of trioxane; sila formals and esters. FARBENFABRIKEN BAYER A.G. 15 March, 1966 [15 April, 1965], No. 11337/66. Headings C3P and C3S. Silicone-containing copolymers are prepared by copolymerizing a formal or a carbonic acid ester of a bis-(hydroxyalkyl) silicon cornpound with trioxane at from 50‹ C. to 120‹ C. in the presence of a cationic initiator. Prefered copolymers are those of trioxane and a compound of the formula where X represents two hydrogen atoms or an oxygen atom, n = 1, 3 or 4, m = 0, 1, 2, 3 or 4 and o = 0 or 1, R 1 is -CH 3 , -O-Si(CH 3 ) 3 Particularly preferred copolymers contain 99À5 to 95À0 mol per cent of trioxane and 0À5 to 5 mol per cent of the formal or carbonic acid ester. A preferred copolymer is with 2,2,8,8-tetramethyl-2,8-disila-1,4,6-trioxa-cyclooctane. In Example 9 the condensation product of bis- (hydroxymethyl)-tetramethyl-disiloxane and pformaldehyde is used. Cationic initiators include strong acids e.g. sulphuric, perchloric, alkane-sulphonic and p-toluene sulphonic acids and Lewis acids e.g. boron trifluoride and its adducts and 2-methyl-1,3-dioxolenium fluoborate. The process may be carried out as an emulsion or solution polymerization in an inert organic liquid. It may be carried out as a bulk copolymerization, the catalyst being melted with the trioxane and the comonomer added simultaneously, or the trioxane being melted initially with the comonomer and then the catalyst added, possibly in an inert solvent. Further comonomers may be employed e.g. ethylene oxide, 1,3-dioxolane, 1,3-oxthiolane, bismethane - sulphonyl - imidazoline or hexamethyl - cyclotrisiloxane. The sila-formals employed in the invention may be obtained by treating bis-(hydroxy alkyl) - silicon compounds with formaldehyde or formaldehyde-yielding substances (e.g. paraformaldehyde or fomals of low-boiling alcohols) in the presence of catalyst e.g. small quantities of strong acid (e.g. p-toluenesulphonic acid or sulphuric acid) with moderate heating, the water which forms being removed by azeotropic distillation with an inert water-immiscible solvent or, in the case of re-acetalization, the volatile alcohol formed being distilled off. The corresponding carbonic acid esters are obtained in a similar manner by reaction with phosgene.

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