采用乙二醛对聚乙烯醇(PVA)纤维预交联后,结合甲醛二次缩醛化处理,得到预交联处理的PVA缩甲醛纤维即高耐热水性能的PVA纤维,并对PVA纤维及预交联前后的PVA缩甲醛纤维进行结构与性能表征。结果表明:经预交联处理的PVA缩甲醛纤维内部结构...采用乙二醛对聚乙烯醇(PVA)纤维预交联后,结合甲醛二次缩醛化处理,得到预交联处理的PVA缩甲醛纤维即高耐热水性能的PVA纤维,并对PVA纤维及预交联前后的PVA缩甲醛纤维进行结构与性能表征。结果表明:经预交联处理的PVA缩甲醛纤维内部结构均匀、致密,结晶度及力学性能较PVA纤维及未经交联的PVA缩甲醛纤维的低,缩甲醛化度较未预交联的PVA缩甲醛纤维的低,但其耐水性能提高,其水中软化点由未预交联的PVA缩甲醛纤维的114℃提高到156℃,所制得的高耐热水性PVA纤维线密度为1.36 dtex,断裂强度为3.48 c N/dtex,断裂伸长率为11.05%。展开更多
The effects of H3PO4 and Ca（H2PO4）2 on compressive strength, water resistance, hydration process of thermally decomposed magnesium oxychloride cement （TDMOC） pastes were studied. The mineral composition, hydration...The effects of H3PO4 and Ca（H2PO4）2 on compressive strength, water resistance, hydration process of thermally decomposed magnesium oxychloride cement （TDMOC） pastes were studied. The mineral composition, hydration products and hydration heat release were analyzed by XRD, FT-IR, SEM and TAM air isothermal calorimeter, etc. After being modified by H3PO4 and Ca（HzPO4）2, the properties of the TDMOC are improved obviously. The compressive strength increases from 14.8 MPa to 48.1 MPa and 37.1 MPa, respectively. The strength retention coefficient （Kn） increases from 0.38 to 0.99 and 0.94, respectively. The 24 h hydration heat release decreases by 10% and 4% and the time of hydration peak appearing is delayed from 1 h to about 10 h. The XRD, FT-IR and SEM results show that the main composition is 5Mg（OH）z＇MgCIz＇8H20 in the modified TDMOC pastes. The possible mechanism for the strength enhancement was discussed. The purposes are to extend the potential applications of the salt lake magnesium resources and to improve the mechanical properties of TDMOC.展开更多
文摘采用乙二醛对聚乙烯醇(PVA)纤维预交联后,结合甲醛二次缩醛化处理,得到预交联处理的PVA缩甲醛纤维即高耐热水性能的PVA纤维,并对PVA纤维及预交联前后的PVA缩甲醛纤维进行结构与性能表征。结果表明:经预交联处理的PVA缩甲醛纤维内部结构均匀、致密,结晶度及力学性能较PVA纤维及未经交联的PVA缩甲醛纤维的低,缩甲醛化度较未预交联的PVA缩甲醛纤维的低,但其耐水性能提高,其水中软化点由未预交联的PVA缩甲醛纤维的114℃提高到156℃,所制得的高耐热水性PVA纤维线密度为1.36 dtex,断裂强度为3.48 c N/dtex,断裂伸长率为11.05%。
基金Project(B0210)supported by One Hundred Talent Project of Chinese Academy of SciencesProject(2008-G-158)supported by Science and Technology Tackling Key Program of Qinghai Province,China
文摘The effects of H3PO4 and Ca（H2PO4）2 on compressive strength, water resistance, hydration process of thermally decomposed magnesium oxychloride cement （TDMOC） pastes were studied. The mineral composition, hydration products and hydration heat release were analyzed by XRD, FT-IR, SEM and TAM air isothermal calorimeter, etc. After being modified by H3PO4 and Ca（HzPO4）2, the properties of the TDMOC are improved obviously. The compressive strength increases from 14.8 MPa to 48.1 MPa and 37.1 MPa, respectively. The strength retention coefficient （Kn） increases from 0.38 to 0.99 and 0.94, respectively. The 24 h hydration heat release decreases by 10% and 4% and the time of hydration peak appearing is delayed from 1 h to about 10 h. The XRD, FT-IR and SEM results show that the main composition is 5Mg（OH）z＇MgCIz＇8H20 in the modified TDMOC pastes. The possible mechanism for the strength enhancement was discussed. The purposes are to extend the potential applications of the salt lake magnesium resources and to improve the mechanical properties of TDMOC.
