略語大辞典 [L] 25 PPA polyphenyl acetylene ポリフェニルアセチレン. 非線型光学材料.polyphenyl acetylene; a π(pi)-electron conjugated amorphous material; easily soluble in organic solvents such as benzene; possesses good air-insensitivity; e.g. used as an NLO(nonlinear optical) material for DFWM(degenerate four-w 丸善「略語大辞典」JLogosID : 11856334