聚甲醛

Flame retardant POM composites were prepared using TPU as carrier to introduce melamine cyanurate into POM matrix, and even dispersion of MCA in polymer matrix was obtained. The prepared flame retardant POM possesses good mechanical properties and flame-retardancy.

采用三聚氰胺氰尿酸盐／聚氨酯复合阻燃剂阻燃聚甲醛，阻燃剂粒子均匀分散于聚氨酯分散相中，解决了阻燃剂与聚甲醛直接共混相容性差、材料性能劣化的难题，获得了阻燃性能和力学性能较好的阻燃聚甲醛材料。

The flame retarding mechanism of MCA on POM was that formaldehyde and formate acid were absorbed by melamine resulting from melamine cyanurate pyrolysis and temperature of burning materials was reduced because melamine cyanurate sublimation absorbed heat and thermalplastic polyurethane absorbed formaldehyde and enhanced stability of POM composites.

热失重、红外和气质联用分析表明，MCA／TPU复合阻燃剂对聚甲醛的阻燃作用是由于三聚氰胺氰尿酸盐高温分解并吸热，降低材料燃烧区域的温度；另一方面MCA高温分解生成的三聚氰胺可吸收聚甲醛分解产生的甲醛和甲酸；此外，TPU可提高聚阻燃甲醛的热稳定性，有利于阻燃。

In the step of hydroxymethylation, gaseous formaldehyde, which was decomposed by paraformaldehyde, was conducted into the reactor. Orthogonal test was designed to investigate the factors of water content in material of PF, reaction temperature, reaction time and consumption of PF on the hydroxymethylation.

在羟甲基化反应中多聚甲醛的进料方式改进为气态进料法，通过正交实验，考察了多聚甲醛原料含水量、反应温度、反应时间、多聚甲醛用量对反应收率的影响。

In this paper,investigation has been made on the process for the synthesis of salicylaldehyde by esterification-oxidation with phenol,paraformaldehyde,boric acid as initial materials.

探索了以苯酚、硼酸和多聚甲醛为原料的酯化氧化法合成水杨醛的工艺路线，根据反应特点，改进了酯化反应方式，采用了多聚甲醛气态解聚法作为羟甲基化反应的进料方式，探讨了羟甲基化反应温度、多聚甲醛原料含水量、催化氧化反应催化剂用量对反应收率的影响并得到最佳反应条件，水杨醛收率为60.5%，纯度达98%以上。

The production technique of polyoxymethylene can be divided into homopolymer technique and copolymer technique. In this project, copolymer technique will be applied.

聚甲醛生产工艺有均聚甲醛和共聚甲醛两种，本项目拟采用共聚甲醛工艺技术。

The crystal structure of trioxane was accurately determinated. By using the crystal structure model of trioxane, the ring-opening polymerization mechanism of trioxane by γ-irradiation may be fairly well explained. Polyoxymethylene obtained by solid state polymerization of trioxane may have two types of molecular chains with different orientations, one parallel to the C...

我们精确测定了三聚甲醛的晶体结构，利用三聚甲醛晶体结构模型，可以很好地阐明三聚甲醛在受到γ射线辐照后开环聚合的机理，由三聚甲醛晶体固相聚合得到的聚三聚甲醛，应该有两种不同取向的分子链，一种与三聚甲醛的c轴平行；另一种与c轴成75°37′的交角。

The non-isothermal crystallization kinetics of polyoxymethyleneand poly- oxymethylene/co-polyamideat different cooling rates were investigated uisng differential scanning calorimetry.

采用差示扫描量热法研究了聚甲醛和聚甲醛/盐聚酰胺二元共混体系在不同降温速率下的非等温结晶行为，并用 Jeziorny 法、Ozawa 法和莫志深法计算了聚甲醛及其共混物的非等温结晶动力学参数。

The forming process for the high-strength, steel-base modified polyformaldehyde composite material in five-laver structure is to melt modified polyformaldehyde by heating and roll to make the melt polyformaldehyde permeate into the gaps gaps between the large-grained spherical copper powder and screw copper nails.

四层结构的钢基铜塑复合材料的成型过程，是将改性聚甲醛加热熔化，经轧制，使熔融的聚甲醛渗透到大颗粒球形铜粉的间隙中，解决了三层材料复合过程中，熔融的聚甲醛水平流动性强过垂直方向的渗透性，造成了结合强度低的缺陷，使聚甲醛层与铜粉及基体结合更牢固，提高了其承载和抗剪切的能力。

The forming process for the high-strength, steel-base modified polyformaldehyde composite material in five-layer structure is to melt modified polyformaldehyde by heating and roll to make the melt polyformaldehyde permeate into the gaps between the large-grained spherical copper powder and screw copper nails.

五层结构的高强度钢基改性聚甲醛复合材料的成型过程，是将改性聚甲醛加热熔化，经轧制，使熔融的聚甲醛渗透到大颗粒球形铜粉的间隙中，解决了三层材料复合过程中，熔融的聚甲醛水平流动性远强过垂直方向的渗透性，造成了结合强度低的缺陷，使聚甲醛层与铜粉、螺旋铜钉及基体结合更牢固，提高了其承载和抗剪切的能力。

The forming process for the high-strength, steel-base modified polyformaldehyde composite material in five-layer structure is to melt modified polyformaldehyde by heating and roll to make the melt polyformaldehyde permeate into the gaps between the large-grained spherical copper powder and screw copper nails.

五层结构的高强度钢基改性聚甲醛复合材料的成型过程，是将改性聚甲醛加热熔化，经轧制，使熔融的聚甲醛渗透到大颗粒球形铜粉与螺旋铜钉的间隙中，解决了三层材料复合过程中，熔融的聚甲醛水平流动性远强过垂直方向的渗透性，造成了结合强度低的缺陷，使聚甲醛层与铜粉、螺旋铜钉及基体结合更牢固，提高了其承载和抗剪切的能力。

This one mode pays close attention to network credence foundation of the businessman very much.

这一模式非常关注商人的网络信用基础。

Cell morphology of bacterial ghost of Pasteurella multocida was observed by scanning electron microscopy and inactivation ratio was estimated by CFU analysi.

扫描电镜观察多杀性巴氏杆菌细菌幽灵和菌落形成单位评价遗传灭活率。