Renewable and safer bisphenol A substitutes enabled by selective zeolite alkylation

Abstract

Sustainable bisphenol A (BPA) substitutes should be safe and renewable to abolish the environmental burden of BPA's endocrine disruption and petrochemical origin. Suitable alternatives preferably also retain the rigid and stiff methylenediphenol (MDP) scaffold to emulate the hallmark performance of BPA-based polymers. Here, we report a holistic solution to sustainable BPA substitutes made from abundant ligninderivable o-methoxyphenols that display low-to-undetectable xeno-estrogenic activity while preserving the MDP scaffold. More speci cally, we propose an innovative zeolite-catalyzed synthesis towards the similar albeit safer methylenediguaiacol (MDG) scaffold via Brønsted acid-catalyzed alkylation of guaiacol with different p-alkenylguaiacols yielding various so-called bisguaiacols. Zeolite catalysis favors regioselectivity and prompts higher rate and chemoselectivity for entropic reasons thanks to active site pocket con nement. Exploiting the intrinsic handles present in o-methoxyphenols not only simpli es and ameliorates classic bisphenol chemistry, but also enables to design out xeno-estrogenic activity.Successful direct reaction of a crude lignin oil extract, as produced by reductive catalytic fractionation, highlights the feasibility and robustness of this route as a downstream process for future wood biore neries. Last but not least, pure p,p'-bisguaiacols are polymerized into high-molecular weight thermoplastic and thermosetting polymers with promising thermo-physical properties. Overall, this work elucidates that renewability should not merely serve as a goal (renewable carbon), but also as a means (safer chemicals), thereby transcending the scope of renewability. 2022TrullemansL. KoelewijnS.F.etal.SupplementaryInformation.docx

Feasibility of wood as a renewable carbon feedstock for the production of chemicals in Europe

“…However, lignin is also a unique polymer consisting of phenolic subunits with various interlinkages and side-chain functionalities. This makes it an ideal precursor for aromatic and phenolic platform chemicals 40,[53][54][55][56][57] if selective depolymerization and/ or conversion can be realized, as is the case with emerging techniques such as lignin-first biorefining. 58 Alternatively, just like celluloses, the (recovered) lignin polymer may also be used directly in multiple applications (e.g., as filler, adhesive) without conversion into chemicals first.…”

Challenges and Opportunities in the Catalytic Synthesis of Diphenolic Acid and Evaluation of Its Application Potential

“…Moreover, it can undergo oxidation and degradation over time [ 39 , 40 ], which can limit its shelf life and usability in several applications, thus requiring careful attention to its stability during the synthesis of the DPA-derived polymers; for instance, when transforming the carboxyl group of DPA in esters, ethers, or amide derivatives [ 41 , 42 ]. To date, DPA has been exploited for the synthesis of epoxy and phenolic resins [ 6 , 43 ] as well as other polymers, such as polycarbonates [ 44 , 45 ], polyarylates [ 46 ], and polyesters [ 47 ]. Both DPA-based epoxy and phenolic resins find applications in the production of composites, adhesives, and coatings [ 48 , 49 ].…”

Investigation into the effect of solvents on lignin hydrogenation for the production of phenolic compounds

“…The shift from fossil to renewable resources can promote the decoupling of chemical production from fossil resources, thereby reducing CO 2 emissions and making the chemical industry greener and more sustainable. 1–3 Lignocellulosic biomass is a kind of non-edible renewable resource largely consisting of cellulose, hemicellulose and lignin. 4,5 The selective and cost-effective conversion of lignocellulosic biomass into fuels and chemicals, aimed at partially or entirely replacing fossil energy sources, is attracting growing attention.…”