An intense and broadband photoluminescence emission is demonstrated in a bio-compatible film produced by thermal annealing of poly(acrylic acid) (PAA). The annealing process enhances the emission intensity from weakly emitting sub-luminophores of C–O and C=O functional groups by a factor of more than two orders of magnitude. The emission property can be sensitively tuned by the annealing temperature, duration, the PAA solution preparation conditions such as solvent type and solvent:PAA ratio. The strong luminescence is attributed to the formation of rigid molecular structure due to aggregation and crosslinking. FTIR measurements show that the aggregation and crosslinking processes subdue nonradiative recombination pathways.

中文翻译：

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退火聚（丙烯酸）中的强可见光发射

在通过聚（丙烯酸）（PAA）热退火生产的生物相容性薄膜中证明了强烈和宽带的光致发光发射。退火过程将 C-O 和 C=O 官能团的弱发光亚发光体的发光强度提高了两个数量级以上。发射性能可以通过退火温度、持续时间、PAA 溶液制备条件（如溶剂类型和溶剂：PAA 比）进行灵敏调整。强烈的发光归因于由于聚集和交联而形成刚性分子结构。FTIR 测量表明聚集和交联过程抑制了非辐射复合途径。