公开(公告)号：DE2645918A1

公开(公告)日：1978-04-13

申请号：DE2645918

申请日：1976-10-12

Applicant: BASF AG

Inventor： DEUSCHEL WALTER DIPL CHEM DR ,  LAY PETER N DIPL ING

IPC: C08F6/00 ,  C08F6/16

Abstract: Extraction of residual monomers from dispersions or suspensions of polymerised materials, and esp. vinyl chloride from PVC prepd. by suspension or emulsion polymerisation comprises subjecting the dispersion or suspension of the polymerised product to a usual extraction to remove unpolymerised vinyl chloride, and when the major portion of residual monomer has been removed from the reactor, i.e. when the effective pressure in the reactor is reduced to 1-4 bars, and without interruption of the extraction, the reactor contents are heated with superheated steam to a final temp. of 70-100 degrees C pref. 80-95 degrees C the increase in temp being >=0.5 degree C/min. pref. 1-2 degrees C/min. so as to attain the desired final temp. at the moment when the effective press in the reactor returns towards 1 bar. The gaseous products comprising steam and vinyl chloride are then removed from the reactor at a pressure corresponding to the vapour press. of water at the final temp. No thermal deterioration of the polymer is caused. Partic. good results are obtd. with vinyl chloride homopolymers and its copolymers with =30% of other monomers e.g. vinyl acetate, vinyl propionate or vinylidene chloride.

公开(公告)号：DE2701352A1

公开(公告)日：1978-07-20

申请号：DE2701352

申请日：1977-01-14

Applicant: BASF AG

Inventor： DEUSCHEL WALTER DIPL CHEM DR

IPC: B01D3/14 ,  C07D307/06

Abstract: The parent patent refers to a method of separating PVC from soln. in THF, in which the water content is adjusted to 10-50 wt. % before distn. In this addn. 0.1-3.0%, wrt. to the water, of a surfactant is also added before distn. The original method effected practically complete recovery of THF leaving a PVC residue which was easily removable from the distn. vessel and easy to filter. Because of the complete separation of tetrahydrofuran the residue was neither noxious nor polluting. However, the method caused a deposit to form on the wall of the distn. vessel which has to be removed mechanically. The addn. of a surfactant eliminates this defect.

公开(公告)号：DE2626124A1

公开(公告)日：1977-12-22

申请号：DE2626124

申请日：1976-06-11

Applicant: BASF AG

Inventor： DEUSCHEL WALTER DIPL CHEM DR ,  LAY PETER DIPL ING

IPC: B01D3/36 ,  C07D307/08 ,  C08F6/10 ,  C07D307/06

Abstract: is polymerised in tetrahydrofuran and PVC extracted by distilling off solvent as azeotrope with H2O. 10-50 (pref. 15-35) wt. % H2O is added to the soln. of vinyl chloride and is distilled at 1 bar press. PVC is left in vessel as reside and extracted by filtration. Process overcomes pollution problems. The pref. solvent is tetrahydrofuran. Solvents can be dioxan, N-Mepyrrolidone, Me2NCHO and Me2SO.

公开(公告)号：DE3123300A1

公开(公告)日：1983-01-05

申请号：DE3123300

申请日：1981-06-12

Applicant: BASF AG

Inventor： DEUSCHEL WALTER DIPL CHEM DR ,  LAY PETER DIPL ING

IPC: C08F6/00 ,  C08F14/06 ,  C08F6/10

Abstract: The invention relates to a process for recovering unreacted vinyl chloride from strongly foaming polyvinyl chloride dispersions by releasing the pressure in the reactor when the polymerisation is complete, returning the foam-form liquid phase which spills out of the reactor during the release of pressure into a separator and returning the liquid phase into the reactor.

公开(公告)号：DE2740209A1

公开(公告)日：1979-03-08

申请号：DE2740209

申请日：1977-09-07

Applicant: BASF AG

Inventor： DEUSCHEL WALTER DIPL CHEM DR ,  DIKOW HERMANN DIPL CHEM DR ,  HAUSZ ALFRED FRIEDRICH DIPL CH ,  OSCHMANN WERNER DIPL CHEM DR ,  SCHAEDLER HUGO DIPL CHEM DR

IPC: C08F2/18 ,  C08F14/06

Abstract: Vinyl chloride is polymerised opt. with is not >30 wt.% of other copolymerisable monomers, in presence of free-radical catalysts, dispersing agents, polymerisation additives, and sorbitan esters. The esters used are liq. at room temp., their acid gps. are derived from branched-chain satd. carboxylic acids, and they have a hydro-lipophile equilibrium value 7 (pref. 3-7). Vinyl chloride is pref. polymerised in a closed system. In such a system polymer solids, e.g. sorbitan mono-palmitate, are not readily introduced. Certain solvents, e.g. toluene, are retained by the polymer; PVC contg. entrained polymer is not suitable for packaging. The method overcomes the problems of solvent retention.