Abstract: The present invention provides an amic acid ester oligomer with the structure of formula (1) wherein R, Rx, G, P and m are as defined in the specification. The present invention also provides a precursor composition for a polyimide resin comprising the above-mentioned oligomer of formula (1). The polyimide synthesized from the precursor composition exhibits good operations and physiochemical properties.

Abstract: The present invention relates to a process for preparing a precursor solution for polyimide/silica composite material and a process for forming a polyimide/silica composite material film on a substrate, comprising adding a monomer of a silane compound to allow a poly(amic acid) to carry a silica moiety; adding a monomer of formula (R6)xSi(R7)(4-x) to allow the silica moiety to carry a photo-polymerizable unsaturated group; and adding a monomer of formula R8N(R9)2 to allow the poly(amic acid) to carry a photo-polymerizable unsaturated group, where R6, R7, R8, R9, and x are as defined in the specification. The present invention also relates to a precursor solution for polyimide/silica composite material and a polyimide/silica composite material. The composite material of the present invention is useful in microelectronic devices, semiconductor elements, and photoelectric elements.

Abstract: A syndiotactic polystyrene composition is improved which exhibits improved crystallization rate. The improved syndiotactic polystyrene composition contains (a) a syndiotactic polystyrene; and (b) a nucleating agent which is selected from the group consisting of two types of compounds represented by the following formulas, respectively: ##STR1## In Formulas I and II, the radicals R.sub.1 and R.sub.2, which can be the same of different, are C.sub.1 to C.sub.5 alkyl groups, X is a halogen group, preferably a bromide group, and n is an integer from 1 to 5. In the present invention, the nucleating agent is provided at 0.01 to 5 part, by weight, per 100 parts, also by weight, of the syndiotactic polystyrene resin. An example of Formula I compound is 2-hydroxybenimidiazole, and an example of the Formula II compound is bis(phenylbromide) methane.