Osaka Noboru, Shibayama Mitsuhiro
Neutron Science Laboratory, Institute for Solid State Physics, The University of Tokyo, Tokai, Ibaraki 319-1106, Japan.
Phys Rev Lett. 2006 Feb 3;96(4):048303. doi: 10.1103/PhysRevLett.96.048303.
The structures of poly(2-(2-ethoxy)ethoxyethyl vinyl ether)-block-poly(2-methoxyethyl vinyl ether) in D2O have been investigated with small-angle neutron scattering (SANS) as a function of temperature T and pressure P. At ambient pressure, the solution underwent a two-step transition at 40 and 65 degrees C, both of which were convex-upward functions of P having a maximum around P0 approximately 150 MPa. The first transition was assigned to a microphase separation to form a bcc structure, and the second was to a macrophase separation. Pressurizing at 28 degrees C resulted in a macrophase separation with divergence at 350 MPa. At 45 degrees C, a reentrant microphase separation was observed by increasing P. Differences in the states of hydrophobic solvation in the low (P<P0) and high pressure regions (P>P0) are discussed based on the SANS structure factors.
采用小角中子散射（SANS）研究了聚（2 - （2 - 乙氧基）乙氧基乙基乙烯基醚）- 嵌段 - 聚（2 - 甲氧基乙基乙烯基醚）在D2O中的结构随温度T和压力P的变化。在常压下，该溶液在40℃和65℃经历了两步转变，这两步转变都是P的上凸函数，在P0约150MPa附近有最大值。第一次转变被认为是微相分离形成体心立方结构，第二次是宏观相分离。在28℃加压导致在350MPa时发生宏观相分离并出现发散。在45℃时，通过增加P观察到再入微相分离。基于SANS结构因子讨论了低压力区域（P < P0）和高压力区域（P > P0）中疏水溶剂化状态的差异。
