Patent GB-1298521-A (GB)
Title: Polymerization process and polymers produced thereby
Inventor: PATTON TAD LE MARRE
IPC: C08G73/00
Filed: 1970-01-19
Abstract: 1298521 1,3 - Imidazolidine - 1,3 - diyl - ring- containing polymers ESSO RESEARCH & ENG CO 19 Jan 1970 [3 Feb 1969 (2)] 2437/70 Heading C3R A polymer has a structure of alternating organic moieties (R) and 1,3-imidazolidine-1,3- diyl rings predominantly or both rings randomly or alternately distributed. The polymer is soluble in dipolar aprotic solvents. The moieties (R) may be aliphatic, alicyclic, and/or aromatic, or derivatives thereof containing functional groups which do not reach with an isocyanate group; such groups may be, e.g. alkyl, aryl, halogen, sulphoxy, sulphonyl, alkoxy, aryloxy, oxo, ester, alkylthio or nitro; but not carboxylic acid, phenol or amine. Moieties (R) may be all the same, or there may be 2 or more different (R), which may be randomly or alternately distributed. (R) may be one or more of the following, or a divalent group formed therefrom: diphenylmethane; diphenyl ether; tetramethylene, hexamethylene, dodecamethylene, or 2,2,4-trimethylhexamethylene, or dipropylether; m- or p-phenylene, biphenylene, 1,5-naphthalene, isophorone, 1,4-cyclohexane, toluene, durene, 4,41-diphenylmethane, 3,3<SP>1</SP>-dimethyl-4,4<SP>1</SP>-biphenylene, 4,4<SP>1</SP>- diphenyl-isopropylidene, m- or p-xylylene, 4,4<SP>1</SP>- methylenebis - (cyclohexyl), cyclohexylphenyl, or benzyl; diphenyl sulphone, diphenyl ether, dimethoxybiphenylene; tetrafluorophenylene; octafluorobiphenyl. The polymer is made by a reaction, initiated by an added CN- catalyst between: (a) HCN and diisocyanate(s); (b) dicyanoformamide(s) and diisocyanate(s); or (c) by polymerization of cyanofonnamidyl isocyanate(s). The catalyst may be NaCN. The dicyanoformamide(s) for (b), and the cyanoformamidyl isocyanate(s) for (c), may each be prepared by reacting diisocyanate(s) and HCN. The solvent is preferably a dipolar aprotic solvent, e.g. dimethyl formamide, dimethylacetamide, dimethyl sulphoxide, or N-methylpyrrolidone. It must be anhydrous. In all processes, the reaction may be initiated at 0-60 C. The temperature may be regulated to 140 C. After the polymerization reaction has subsided, a tertiary amine may be added which catalyses the ring-closure of cyanoformylurea groups to imidazolidine ring. Examples are triethylamine, trimethylamine, N- methyl morpholine, N-methyl piperidine, or triethylene triamine; or N,N-dialkylanilines, pyridine, picoline or lutidine. There may be 0À0005-0À05 molar equiv. of amine based on isocyanate groups. The solution temperature is preferably 20-90 C. Precipitation of the polymer. Before the polymer is pptd., an active solvent may be added, e.g. alcohol or primary or secondary amine, to eliminate the isocyanate groups, to prevent cross-linking with the heterocyclic imino groups. The polymer is then pptd. by pouring into either a non-reactive solvent, e.g. benzene, toluene or acetone, or into a reactive solvent which reacts with the terminal isocyanate groups, e.g. an alkanol, primary or secondary amine, H 2 O, or NH 4 OH. Use.-Films, fibres, foams, moulded objects, laminates or electrical insulators. Films may be made by forming under heat and pressure, or by casting from solution, e.g. in dimethyl formamide.