超速升温对玻璃态聚偏氟乙烯结晶的影响

EFFECT OF HIGH-RATE HEATING ON THE CRYSTALLIZATION OF GLASS STATE POLY(VINYLIDENE FLUORIDE)

我们曾研究超速淬火温度对聚偏氟乙烯(PVF_2)薄膜结晶结构的影响,在不同温度下淬火可分别得到α、β和γ三种晶型结构。本工作从非晶的玻璃态PVF_2出发,通过超速升温的方法,进一步研究结晶温度对PVF_2晶型结构的影响。

Crystalline polymorphs from the glass state of poly (vinylidene fluoride)(PVF_2)inducedby high-rate heating have been studied by FTIR and TEM. The glass state PVF_2 samplewas obtained by ultraquenching the thin films into liquid nitrogen. Three kinds of poly-morphs were formed when the sample was heated very quickly to higher temperatures withsubsequent isothermal crystallization. High-rate warming the glass to the temperatures below30℃ results in formation of βphase microcrystals. When the glass is heated very quicklyto 150℃ predominantly the α phase lamellae or spherulites were obtained, while at temp-eratures of 40-70℃,the βphase and αphase coexisted. If the temperature of high-rate heatingwas upto 165℃, the perfect spherulites of γphase PVF_2 were observed.