A method for the synthesis of polyphosphosiloxane by the thermal condensation of an equimolar mixture of trimethyl phosphate and (3-aminopropyl)triethoxysilane at 200 °C was developed. The reaction affords ethanol and polyphosphosiloxane-Si(OEt)[(CH2)3NR1R2]-O-P(O)(OMe)-O}n-(R1 = H, Me; R2 = Me), whose composition and structure were confirmed by 1H, 13C, and 31P NMR spectroscopy, IR spectroscopy, and elemental analysis. The scheme of polymerization involving the intermediate formation of methyl-and dimethylphosphoric acids and their condensation with ethoxysilanes was proposed. The calcination of the obtained polyphosphosiloxane in vacuo at 350 °C results in the elimination of the amino groups and alkoxide substituents, and a spatially cross-linked polymer is formed as an amorphous powder. Its further thermolysis at 600 and 1000 °C gives crystalline phosphosilicates Si5O(PO4)6 or SiP2O7. Their amorphous and crystalline samples were characterized by IR spectroscopy, X-ray diffraction analysis, and solid-state 13C and 31P spectroscopy.
开发了一种通过在200°C下对等摩尔的三甲基
磷酸酯和(3-
氨丙基)三乙氧基
硅烷进行热缩合合成聚
磷硅氧烷的方法。反应生成
乙醇和聚
磷硅氧烷-Si(OEt)[(
CH2)3NR1R2]-O-P(O)(OMe)-O}n-(R1 = H, Me; R2 = Me),其组成和结构通过1H、13C和31P核磁共振光谱、红外光谱和元素分析得到确认。提出了一种聚合机制,涉及甲基和
二甲基磷酸的中间体形成及其与乙氧基
硅烷的缩合。将获得的聚
磷硅氧烷在真空下于350°C煅烧,将导致
氨基和醇氧基取代基的去除,形成作为无定形粉末的空间交联聚合物。在600°C和1000°C下进一步热解会产生晶体
磷硅酸盐Si5O(PO4)6或SiP2O7。其无定形和结晶样品通过红外光谱、X射线衍射分析及固态13C和31P光谱进行了表征。