Polymerization of alcohol solutions of formaldehyde to produce high molecular weight polyoxymethylene

Claim 1

THE PROCESS OF POLYMERIZING AN ALCOHOLIC SOLUTION OF FORMALDEHYDE WHICH COMPRISES FORMING A STARTING SOLUTION OF FORMALDEHYDE, AN ALCOHOL, AND A NON-AROMATIC AMINE FREE OF CARBONYL GROUPS AND OF NITRO GROUPS AND HAVING A PKB OF LESS THAN 7 AS A POLYMERIZATION CATALYST, THE PH OF SAID STARTING SOLUTION BEING FROM 3.5 TO 10.0, ADJUSTING THE TEMPERATURE, PRESSURE AND FORMALDEHYDE CONCENTRATION OF SAID SOLUTION SUCH THAT THE SAID CONCENTRATION IS FROM 25%-85% BY WEIGHT OF FORMALDEHYDE BASED ON THE TOTAL WEIGHT OF ALCOHOL AND FORMALDEHYDE, AND THE SAID SOLUTION IS SUFFICIENTLY SUPERSATURATED WITH RESPECT TO FORMALDEHYDE THAT POLYOXYMETHYLENE SEED PARTICLES FORM SPONTANEOUSLY THEREIN, MAINTAINING THAT SUPERSATURATED CONDITION UNTIL SAID SOLUTION BECOMES VISIBLY CLOUDY WITH SEED PARTICLES, PLACING SAID SEED PARTICLES IN A REACTION MEDIUM COMPRISING FORMALDEHYDE, ALCOHOL AND AND A NON-AROMATIC AMINE FREE OF CARBONYL GROUPS AND OF NITRO GROUPS AND HAVING A PKB OF LESS THAN 7, THE TEMPERATURE OF SAID REACTION MEDIUM BEING FROM 60*C. TO 125* C., THE PH OF SAID REACTION MEDIUM BEING FROM 3.5-10, THE FORMALDEHYDE CONCENTRATION OF SAID REACTION MEDIUM, AT THE REACTION TEMPERATURE AND PRESSURE, BEING FROM ABOUT 0.5% TO ABOUT 7.0% GREATER THAN THE WEIGHT PERCENTAGE OF FORMALDEHYDE REQUIRED TO SATURATE SAID REACTION MEDIUM WITH RESPECT TO FORMALDEHYDE BUT LESS THAN THE LOWEST CONCENTRATION AT WHICH SEED PARTICLES OF POLYOXYMETHYLENE FORM SPONTANEOUSLY THEREIN, AND MAINTAINING THE REACTION TEMPERATURE, PRESSURE, AND FORMALDEHYDE CONCENTRATION OF SAID REACTION MEDIUM FOR A PERIOD OF TIME SUFFICIENT FOR SAID SEED PARTICLES TO GROW TO A NUMBER AVERAGE MOLECULAR WEIGHT OF AT LEAST 15,000.