研究了聚甲醛制备过程中引发剂质量分数、物料配比及反应温度等对聚甲醛中低分子甲醛的影响，并最终制备出低挥发分聚甲醛。研究结果表明，在反应温度为89℃、引发剂质量分数为50 μg/g时，聚甲醛GM最低，同时，采用引发剂与二氧五环先期进行聚合，能够有效降低聚甲醛中的小分子甲醛，提升聚甲醛的热分解温度，此时，聚甲醛性能比研究前具有明显提升，拉伸强度、缺口冲击强度、弯曲强度分别达到61.3、90.3、6.71 MPa；聚甲醛GM为78 μg/g，能够满足汽车等行业对于低挥发分聚甲醛的要求。同时，封端剂及封端剂用量对聚甲醛的GM具有较大影响，当封端剂质量分数为1 300 μg/g时，活性中心及不稳定末端基基本达到完全钝化的目的。

Polyoxymethylene (POM) with lower volatile matters is prepared and the effects of the mass content of initiator,the ratio of raw materials and reaction temperature on low molecular formaldehyde in prepared POM are investigated.It is shown that the content of low molecular formaldehyde in prepared POM can reach the minimum when reaction temperature is set at 89℃ and the content of initiator is 50 μg·g^-1.Meanwhile,the pre-polymerization between initiator and dioxolane can reduce effectively the content of low molecular formaldehyde in prepared POM and enhance the decomposition temperature of POM.Through these improvements,POM performance improves significantly,and the tensile strength,notched impact strength and flexural strength of samples are 61.3 MPa,90.3 MPa and 6.71 MPa respectively.The content of low molecular formaldehyde is as low as 78 μg·g^-1,which can meet the requirements from the automotive and other industries.It is found that the type and dosage amount of blocking agent has a great impact on the content of low molecular formaldehyde in POM.The active center and the unstable terminal group are completely passivated when the dosage amount of blocking agent is 1 300 μg·g^-1.