| 摘要 |
Oxymethylene polymers containing oxymethylene groups and groups of greater stability are stabilized by subjecting the polymer in solid particulate form to treatment with a liquid medium comprising trioxane together with water and/or an organic hydroxyl compound at a temperature high enough to cause the polymer particles to swell in the liquid medium but too low to cause them to become tacky and so show a tendency to agglomerate. The liquid medium may contain an aldaline material, e.g. ammonia, and less than 40% trioxane. Copolymers, or terpolymers, containing also cyclic ethers are specified, as are oxymethylene homopolymers which have been end-capped with such stable groups as ether groups. |
