The bondline chromatic alteration of poly(vinyl acetate) (PVAc) in wood assemblies has an appreciable impact on the aesthetic characteristic of these products (mostly important for panels used in furniture). While the origin of this phenomenon has been explained for the cases of pure polymers and wood substrates alone, present work investigates about the origin of discoloration for the case of bondlines prepared with selected wood species (cherry and maple) and two commercial PVAc dispersions, one containing and one not containing aluminum ions. Assemblies were exposed to temperature and UV light. The comparison (carried out through GC-MS analysis) among the compounds extracted by these species before and after exposure allowed identifying specific flavonoids that were used as model-compounds to replicate the discoloration process in laboratory. Thus, using spectrophotometric measurements and TLC analysis it is shown that discoloration is related to the presence of aluminum in the dispersion, whose interaction with flavonoids in wood generates different forms of complexes that can be modified upon irradiation and emitting in the visible range. Although the specific involved compounds are species-related, it can be suggested that the identified mechanism at the basis of discoloration in PVAc-wood bondlines has general validity.

木质组件中聚醋酸乙烯酯（PVAc）的粘合线颜色变化对这些产品的美学特性（对家具中的面板最为重要）具有明显影响。虽然仅针对纯聚合物和木质基材的情况已解释了这种现象的起源，但目前的工作是针对使用选定的木材物种（樱桃和枫木）和两种市售PVAc分散体制备的粘结层的变色起因进行调查的，其中一种含有和不含铝离子的一种。将组件暴露于温度和紫外线下。在暴露之前和之后，这些物种提取的化合物之间的比较（通过GC-MS分析进行）可以确定特定的类黄酮，这些类黄酮用作模型化合物以复制实验室的变色过程。因此，使用分光光度法测量和TLC分析表明，变色与分散液中铝的存在有关，铝与木材中类黄酮的相互作用产生了多种形式的配合物，这些配合物可以在可见光范围内进行辐照和发射后进行修饰。尽管具体涉及的化合物是与物种相关的，但可以认为，以PVAc-木材粘合线变色为基础的确定机理具有普遍的有效性。