Increasing the Scale and Decreasing the Cost of Making a Catechol-Containing Adhesive Polymer

Achieving adhesive bonding in wet environments remains a significant challenge in both day-to-day life and industrial applications. Inspired by how marine shellfish stick to rocks, a wide variety of innovative polymer adhesives containing catechol moieties have been developed by several research groups. Despite displaying impressive performance, these adhesives have not yet emerged on the market. Difficulties associated with translating small-scale academic research to industrial production have persisted. In this paper, we focus our attention on poly­(vinylcatechol-styrene), a biomimetic polymer that has shown considerable bonding in both dry and underwater conditions. Herein, we tackled three issues to help bring this polymer beyond academic laboratories: monomer sourcing, polymerization processes, and deprotection steps. Thus, we propose a new route to produce poly­(vinylcatechol-styrene) made of (i) a 3,4-dimethoxystyrene monomer preparation from 3′,4′-dimethoxyacetophenone, a low-cost and high-availability reagent, (ii) a suspension polymerization to yield the intermediate poly­(3,4-dimethoxystyrene-styrene) at the large scale, and (iii) an iodocylohexane-induced methyl cleavage to obtain the final poly­(vinylcatechol-styrene). In our laboratory, we could synthesize this adhesive polymer at up to 60 g scales, avoided harsh reaction conditions, and reduced the cost of the polymer by half. Cost calculations are described both for materials only and also when considering labor and energy. An unexpected bonus was improved performance in both dry and wet conditions.