Thermotropic copolymers of 4,4'-biphenyldicarboxylic acid
申请人:The Dow Chemical Company
公开号:US05037938A1
公开(公告)日:1991-08-06
The invention relates to a class of polyesters and copolyesters which display optical anisotropy in the molten state and to the shaped articles, fibers and films obtained from the optically anisotropic melts. The copolyesters consisting essentially of recurring structural units (a) independently each occurrence selected from the group consisting essentially of Formula I; recurring structural units (b) independently each occurrence selected from the group consisting of Formulas II and III; recurring structural units (c) independently each occurrence selected from the group consisting of Formula IV and optionally recurring structural units (d) independently each occurrence selected from the group consisting of Formula V: ##STR1## wherein R independently each occurrence is selected from the group consisting of hydrogen, halo, lower alkyl, methoxy and phenyl; R' independently each occurrence is selected from the group consisting of hydrogen, halo, methoxy and phenyl; and R" comprises lower alkyl.
Melt processable thermotropic aromatic copolyesters and process for preparing same
申请人:THE DOW CHEMICAL COMPANY
公开号:EP0399349A2
公开(公告)日:1990-11-28
Disclosed is a copolymer capable of forming an optically anisotropic melt comprising recurring structural units of Formulas I, II III; and IV and optionally V:
wherein each R is independently hydrogen, halogen, lower alkyl, methoxy or phenyl; R¹ is loweralkyl; R² is independently hydrogen, halogen, methoxy or phenyl. The present invention also relates to a process for preparing the copolymer. The copolymers of the present invention usually have a low melting point below 350°C and can be readily melt extruded into fibers, films or the like.
本发明公开了一种可形成光学各向异性熔体的共聚物,该共聚物由式 I、II III、IV 和可选的 V 的重复结构单元组成:
其中每个R独立地是氢、卤素、低级烷基、甲氧基或苯基;R¹是低级烷基;R²独立地是氢、卤素、甲氧基或苯基。本发明还涉及制备共聚物的工艺。本发明的共聚物通常熔点较低,低于 350°C,易于熔融挤压成纤维、薄膜等。
Hempel, Erika; Lindau, Juergen; Roetz, Uwe, Molecular Crystals and Liquid Crystals (1969-1991), 1990, vol. 193, p. 199 - 204
作者:Hempel, Erika、Lindau, Juergen、Roetz, Uwe、Fischer, Hartmut、Utschick, Hermann、Kuschel, Frank
DOI:——
日期:——
Liquid crystalline epoxy nanicomposite material and application thereof
申请人:Su Wei-Fang
公开号:US20110009521A1
公开(公告)日:2011-01-13
The invention provides an epoxy nanocomposite material for dental therapy, which can be applied to direct or indirect clinical restoration, dental core-post system, and dental brace etc. The epoxy nanocomposite filling material provided by the invention can be polymerized with various curing agents to form the polymer with low shrinkage.
OPTICAL FILM, CIRCULARLY POLARIZING PLATE AND ORGANIC ELECTROLUMINESCENT DISPLAY DEVICE
申请人:KONICA MINOLTA, INC.
公开号:US20160070030A1
公开(公告)日:2016-03-10
Provided is an optical film containing a cellulose derivative, the optical film having an in-plane retardation Ro
550
within the range of 120 to 160 nm measured at a wavelength of 550 nm under an atmosphere of a temperature of 23° C. and a relative humidity of 55%, and a ratio Ro
450
/Ro
550
within the range of 0.65 to 0.99, Ro
450
/Ro
550
being a ratio of an in-plane retardation Ro
450
measured at a wavelength of 450 nm to the in-plane retardation Ro
550
measured at a wavelength of 550 nm, wherein, a substituent of a glucose skeleton in the cellulose derivative satisfies the requirements (a) and (b) which are described in the specification, and the optical film contains a compound A satisfying the following condition defined by Expression (a1) which is described in the specification.