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公开(公告)号：AT127482T
公开(公告)日：1995-09-15
申请号：AT88101595
申请日：1988-02-04
Applicant: HOECHST AG
Inventor： SEXTRO GUENTER DR , MUECK KARL-FRIEDRICH DR , BURG KARLHEINZ DR , FISCHER EBERHARD DR
Abstract: A continuous process for removing unstable components from crude oxymethylene copolymers still containing catalysts, monomeric starting materials and unstable components, by treating the copolymers with deactivators, optionally in the presence of assistants, in a pressure zone and subsequently removing volatile components in a decompression zone, optionally in the presence of stabilisers, where the crude polymers are fully melted in the absence of deactivators and assistants immediately after completion of the polymerisation step, and the deactivators, either alone or together with assistants, are subsequently incorporated into the resultant polymer melt under pressure in at least one pressure zone. … This process avoids degradation and gives significantly better properties. … …
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公开(公告)号：DE59500588D1
公开(公告)日：1997-10-09
申请号：DE59500588
申请日：1995-06-23
Applicant: HOECHST AG
Inventor： HOFFMOCKEL MICHAEL DR , SEXTRO GUENTER DR , EMIG GERHARD PROF DR , KERN FRANK DR
IPC: B01J27/19 , B01J27/228 , B01J32/00 , C07B61/00 , C07D323/06
Abstract: In the prodn. of trioxane from HCHO in the gas phase, the catalyst comprises tungsto-molybdophosphoric acid (I) of the compsn.: H3PWnMomO40.xH2O (I); n, m = 4-8; n + m = 12; x = 0-32.
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公开(公告)号：DE4431575A1
公开(公告)日：1996-03-07
申请号：DE4431575
申请日：1994-09-05
Applicant: HOECHST AG
Inventor： FLEISCHER DIETRICH DR , HOFFMOCKEL MICHAEL DR , MUECK KARL-FRIEDRICH DR , SEXTRO GUENTER DR
Abstract: Prodn. of acetal copolymers with simultaneous end gp. stabilisation is effected in homogeneous phase by copolymerising cyclic formaldehyde oligomers with cyclic acetal cpds. in a polymerisation reactor with addn. of a basic substance to deactivate the initiator following the copolymerisation, the process being such that the prod. (with its non-stable chain end content in presence of residual monomers reduced to 0.01-1%) is passed to a granulator where the bulk of the residual monomer is lost and the remaining residual monomers and dissolved impurities are removed by solvent extn. prior to drying and stabilising the prod. and then granulating it.
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公开(公告)号：DE4244582A1
公开(公告)日：1994-07-07
申请号：DE4244582
申请日：1992-12-31
Applicant: HOECHST AG
Inventor： HOFFMOCKEL MICHAEL DR , MUECK KARL-FRIEDRICH DR , SEXTRO GUENTER DR , EMIG GERHARD PROF DR , KRUEGER BENNO DR , KERN FRANK DIPL ING
IPC: C07D323/06
Abstract: In the prodn. of trioxane (I) from HCHO in the gas phase, vanadyl hydrogen phosphate hemihydrate (II) is used as catalyst.Pref. (II) is in water-depleted form and is activated with steam (24 h to 14 days at 100-200 deg.C). Reaction is carried out with dry HCHO at 80-150, esp. 100-120 deg.C and 0.5-5, esp. 0.5-2 bar, opt. with addn. of a carrier gas (N2). In an example, the selectivity has 1 (no by-prods. formed) if 0.43 mole/h HCHO + 1.8 mole/h N2 were passed through a reactor contg. 82 g (II) pellets at 80 deg. C; the conversion was 22.1%, i.e. 62.8% of the equilibrium conversion, and throughput 35.3 kg/cu.m.h.
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公开(公告)号：DE4443673A1
公开(公告)日：1996-06-13
申请号：DE4443673
申请日：1994-12-08
Applicant: HOECHST AG
Inventor： HOFFMOCKEL MICHAEL DR , SEXTRO GUENTER DR
Abstract: A method for suppressing condensation reactions in the end gp.-stabilisation of acetal copolymers (I) in aq. or aq.-alcoholic soln. comprises deactivating the metal surfaces of the reactor at 130-200 deg C with 0.05-50 ppm alkali phosphate (w.r.t. amt. of soln. used).
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Patent Agency Ranking
公开(公告)号：DE3854405D1
公开(公告)日：1995-10-12
申请号：DE3854405
申请日：1988-02-04
Applicant: HOECHST AG
Inventor： SEXTRO GUENTER DR , MUECK KARL-FRIEDRICH DR , BURG KARLHEINZ DR , FISCHER EBERHARD DR
Abstract: A continuous process for removing unstable components from crude oxymethylene copolymers still containing catalysts, monomeric starting materials and unstable components, by treating the copolymers with deactivators, optionally in the presence of assistants, in a pressure zone and subsequently removing volatile components in a decompression zone, optionally in the presence of stabilisers, where the crude polymers are fully melted in the absence of deactivators and assistants immediately after completion of the polymerisation step, and the deactivators, either alone or together with assistants, are subsequently incorporated into the resultant polymer melt under pressure in at least one pressure zone. … This process avoids degradation and gives significantly better properties. … …
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公开(公告)号：CH628657A5
公开(公告)日：1982-03-15
申请号：CH551477
申请日：1977-05-03
Applicant: HOECHST AG
Inventor： SEXTRO GUENTER DR , BURG KARLHEINZ DR , SCHLAF HELMUT DR , SABEL HANS-DIETER DR , HELLER ALWIN
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公开(公告)号：DE2843468A1
公开(公告)日：1980-04-24
申请号：DE2843468
申请日：1978-10-05
Applicant: HOECHST AG
Inventor： MUECK KARL-FRIEDRICH DR , SEXTRO GUENTER DR , BURG KARLHEINZ DR
IPC: B01J27/00 , C07B61/00 , C07D317/12 , C07D323/06
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公开(公告)号：CH606163A5
公开(公告)日：1978-10-31
申请号：CH1646774
申请日：1974-12-11
Applicant: HOECHST AG
Inventor： SEXTRO GUENTER DR , BURG KARLHEINZ DR , DUERICHEN KLAUS DR
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公开(公告)号：CH606162A5
公开(公告)日：1978-10-31
申请号：CH1665274
申请日：1974-12-13
Applicant: HOECHST AG
Inventor： SEXTRO GUENTER DR , HAEFNER KARL-HEINZ DR , BURG KARLHEINZ DR
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