The invention generally relates to shape memory films that are tri-functionally crosslinked and that comprise multiple, non-terminal, phenylethynyl moieties. In addition, the present invention relates methods of fabricating such films. Due to the improved properties of such SMPs, the SMP designer can program in to the SMP thermomechanical property enhancements that make the SMP suitable, among other things, for advanced sensors, high temperature actuators, responder matrix materials and heat responsive packaging.

Polymer resins for the vat photopolymerization of thermoplastics are provided, in particular for the vat photopolymerization of thermoplastics with exception thermal stability and mechanical properties. In some aspects, the polymer resins are prepared by ring opening of an aromatic dianhydride with an alcohol containing an acrylate or methacrylate to produce a photocrosslinkable diacid monomer; conversion of the photocrosslinkable diacid monomer to a photocrosslinkable diacyl chloride; and polymerization of the photocrosslinkable diacyl chloride with an aromatic diamine to produce a photocrosslinkable precursor polymer. Upon crosslinking and drying, a thermal imidization can yield aromatic polyimide polymers with high yield and with micron-scale structural resolution.

A transparent polyimide film, prepared from a copolymerized polyamide acid according to a chemical cyclization method, is provided. The copolymerized polyamide acid requires at least a semi-aromatic polyamide acid, and the semi-aromatic polyamide acid is formed by reacting cyclobutane-1,2,3,4-tetracarboxylic dianhydride (CBDA) and 2,2′-bis(trifluoromethyl)diaminodiphenyl (TFMB). The molar number of dianhydrides of the semi-aromatic polyamide acid is more than 20% of the total molar number of anhydrides of the copolymerized polyamide acid, so that the transparent polyimide film has a light transmittance greater than 80%, a chroma b* less than 5, and a CTE less than 35 ppm/° C.

The invention generally relates to shape memory films that are tri-functionally crosslinked and that comprise multiple, non-terminal, phenylethynyl moieties. In addition, the present invention relates methods of fabricating such films. Due to the improved properties of such SMPs, the SMP designer can program in to the SMP thermomechanical property enhancements that make the SMP suitable, among other things, for advanced sensors, high temperature actuators, responder matrix materials and heat responsive packaging.

The invention generally relates to shape memory films that are tri-functionally crosslinked and that comprise multiple, non-terminal, phenylethynyl moieties. In addition, the present invention relates methods of fabricating such films. Due to the improved properties of such SMPS, the SMP designer can program in to the SMP mechanical property enhancements that make the SMP suitable, among other things, for advanced sensors, high temperature actuators, responder matrix materials and heat responsive packaging.

A resin sheet is made using a resin composition containing a thermosetting component (A). The thermosetting component (A) contains a maleimide resin. A thermal diffusion rate of the thermally cured resin sheet is 1.0 × 10.sup.-6 m.sup.2/s or more. The resin sheet has a thickness in a range from 5 .Math.m to 120 .Math.m .

Phthalonitrile adhesive formulations are provided. Such an adhesive formulation may comprise an etherimide-phthalonitrile oligomer having formula

##STR00001## wherein R.sub.1 is an unsubstituted or substituted aryl group or an unsubstituted or substituted cycloalkyl group; R.sub.2 is an unsubstituted or substituted aryl group and n has a value of from 1 to 30. Also provided are methods of making and using the adhesive formulations.

Polymer resins for the vat photopolymerization of thermoplastics are provided, in particular for the vat photopolymerization of thermoplastics with exception thermal stability and mechanical properties. In some aspects, the polymer resins are prepared by ring opening of an aromatic dianhydride with an alcohol containing an acrylate or methacrylate to produce a photocrosslinkable diacid monomer; conversion of the photocrosslinkable diacid monomer to a photocrosslinkable diacyl chloride; and polymerization of the photocrosslinkable diacyl chloride with an aromatic diamine to produce a photocrosslinkable precursor polymer. Upon crosslinking and drying, a thermal imidization can yield aromatic polyimide polymers with high yield and with micron-scale structural resolution.

Curable polyimides and compositions thereof with very good dielectric properties are provided. Prepregs of these compositions laminated with copper foil to prepare copper clad laminates having Tg>150 C and Df<0.0025 are also provided.

The thermosetting resin composition, a prepreg containing same, a metal foil-clad laminate and a printed circuit board; the resin composition comprises the following components: a combination of a bismaleimide resin and a benzoxazine resin or a prepolymer of a bismaleimide resin and a benzoxazine resin, an epoxy resin and an active ester. A metal foil-clad laminate prepared by using the resin composition provided by the present invention has a high glass transition temperature, a low thermal expansion coefficient, a high high-temperature modulus, a high peel strength, a low dielectric constant, a low dielectric loss factor, as well as good heat resistance and good processability.