Photocure properties of high‐heat‐resistant photoreactive polymers with cinnamate groups

Abstract

New high-heat-resistant photoreactive polymers with cinnamate groups were synthesized by the reaction of cinnamic acid (CA) and epoxy resins. Their photocure properties were investigated with Fourier transform infrared spectroscopy, UV-visible spectroscopy, and thermogravimetric analysis (TGA). Their photocure reaction rates and the extent of reaction conversion increased with the intensity of UV irradiation. To investigate their photocure reaction kinetics, their reaction conversion rates were plotted against reaction conversion so that their photocure reactions could be analyzed in terms of an nth-order kinetics reaction equation. The YX4000H-CA photoreactive polymer with a biphenyl moiety, which was expected to have strong molecular interactions, showed a lower reaction conversion rate and reaction constant, and the highest reaction conversion rate and reaction constant was observed in XP2030-CA with an optimum cure reaction space and a reduction of molecular interactions compared with the other photoreactive polymers. Thermal stability was studied by observation of the changes in the transmittance of the photocured polymer films upon heating and by measurement of the weight loss with temperature with TGA. These photoreactive polymers showed good thermal properties, with almost no transmittance change in the visible range even after they were heated at 2508C for 1 h, and they exhibited little weight loss up to about 2508C.

UV‐laser formation of 3D structures based on thermally stable heterochain polymers

“…Along with this fact, however, an intermolecular interaction of the СС bonds of the active solvent or DAAD with the NH groups of m ‐PA with the formation of the grafted copolymers was possible. It needs to note that the maximal thermal stability of the obtained materials in air exceed the analogous characteristic (about 250 °C) of a cured PPC (in the form of the cast films) based on end‐capped aromatic diglycidyl ethers and cinnamate esters of polyphenylenes with the bridge aliphatic groups …”

“…It needs to note that the maximal thermal stability of the obtained materials in air exceed the analogous characteristic (about 250 8C) of a cured PPC (in the form of the cast films) based on end-capped aromatic diglycidyl ethers and cinnamate esters of polyphenylenes with the bridge aliphatic groups. 31…”

A finite element method for light activated shape‐memory polymers

“…Phenomenological relations may be found in the literature for the evolution of α . The evolution of α while the second network forming is given by where k f is the rate constant of the forward reaction and n is the order of the reaction.…”

“…Phenomenological forms. Phenomenological relations may be found in the literature ( [29,44]) for the evolution of˛. The evolution of˛while the second network forming is given by…”

Photocure Reactions of Photoreactive Prepolymers with Cinnamate Groups

“…The most significant challenges have been in the area of improving the thermal resistance, transparency, and cost effectiveness of CF resists for color patterning, because the pigment dispersion method, which is the widely used CF manufacturing process, requires these properties. [2][3][4] In previous reports, 5,6 new methacrylate-type pre-polymers including a cyclohexane moiety and biphenyl group, and new cinnamate-type photoreactive pre-polymers with a cyclopentadiene moiety and various aromatic groups were synthesized in order to improve the heat resistance and transparency of photopolymer systems.…”