Howard G. Rogers

Amorphous rigid-rod polymers

Synthese de tels polyamides, polyesters et polyesteramides influence de la structure moleculaire sur les proprietes optiques et morphologiques

High Refractive Index Polymers

Ethylenically unsaturated polymerizable acrylic (or methacrylic) monomers having pendant halogenated carbazole moieties, useful for the production of high refractive index polymers, are disclosed. The monomers are useful for the bonding of optical elements in the fabrication of optical devices.

Novel thermotropic polyesteramides

Abstract A series of wholly aromatic, para-linked, thermotropic polyesteramides has been synthesized from various aminophenols, 2-trifluoromethyl terephthalic acid, and 2,2′-trifluoromethyl-4,4′-biphenyl dicarboxylic acid. The polymers exhibit good solubility and, in most cases, low mesophase transition temperatures. Oriented films of these materials show a high degree of optical anisotropy. The infrared dichroic behavior of the amide carbonyl was used to calculate orientation as well as a new value for the angle of the ester carbonyl vibrational transition moment.

Consequences of chemical modification on optical and solution properties of rodlike polyamides

Abstract Rodlike polyamides were substituted to 50–55% on the nitrogen atom of the amide group with benzyl, 1-naphthylmethyl, and 4-(1,3,6,8-tetrabromo-9-carbazolyl)-1-butyl groups using a standard literature procedure. The resulting polymers exhibit significantly lower isotropic refractive indices and enhanced solubility. Polymers composed of the isophthaloyl moiety, with or without N-substitution, also exhibit lower refractive indices and enhanced solubility when compared to their rodlike analogs. These differences in properties are due to a great extent to the large difference in conformational rigidity between the two polymer types.

Linear unsaturated polyamides and polyhydrazides

Abstract Polyhydrazides and polyamides were prepared from hydrazine, piperazine, or substituted piperazines and muconic or α,α′ -dimethylmuconic acid chlorides by interfacial and solution polymerization. Low-temperature solution polymerization was preferred for polyhydrazides, and the interfacial technique for the piperazides. Polymers of dimethylmuconic acid exhibited better properties than those of muconic acid, e.g., molecular weight, film strength, and solubility. Optical properties, such as transparency, color, refractive index, and birefringence, were also determined and compared to aromatic polyamides and hydrazides.