The Journey of Phenolics from the First Spark to Advanced Materials

Abstract

The emergence, historical and recent developments of phenolic resins are reviewed. The history of the invention of the first man made plastics and a short bibliography of the inventor Leo H. Baekeland is provided. Moreover, the basic chemistry of phenol‐formaldehyde resins, as synthesis of resol and novolak, their structures, variations, and curing are discussed. Modification of these resins and molecular designs for specific applications in retro perspective are highlighted. This review also provides a comprehensive account on the development of benzoxazine resins as an alternative to classical phenolics. In addition to the benzoxazine synthesis and their curing mechanism, special monomers and polybenzoxazine precursors as curable thermoplastics are reviewed. Besides classical chemicals, the potential of renewables for phenolic resin production is also highlighted. Finally, the relative advantages and disadvantages of these systems are discussed and their future potentials are presented.

Advanced Thermosets from Sulfur and Renewable Benzoxazine and Ionones via Inverse Vulcanization

“…Classical phenolic resins, novolac and resol, are the first manmade polymers found many different applications in the last century ranging from ordinary commodity goods to blast protection materials. According to the production volumes, these resins will definitely survive in polymer science in the second century of their existence. − On the other hand, classical phenolic resin producers are struggling with the regulations for formaldehyde emissions and byproduct release during curing that cause health and environmental issues. Thus, efforts are focused on a satisfactory solution to these drawbacks .…”

Aromatic dialdehyde-based bisbenzoxazines: The influence of relative position of oxazine rings

“…Benzoxazines (BZX) are an interesting class of phenolic thermoset, which has gained increased attention during the last thirty years. [1] Their outstanding properties such as high thermal stability, initiator-free thermally activated polymerization and curing, and their relatively easy syntheses are some of the reasons that make BZX interesting from both academic and industrial communities. Among these properties of interest, the char formation at high temperature is desirable in the manufacturing of high performance thermosets, used in aerospace industry.…”

Catalyzing the Ring-Opening Polymerization of 1,3-Benzoxazines via Thioamide from Renewable Sources

“…In the last century, phenol–formaldehyde resins as the first man-made polymers, particularly novolac and resol, found many applications in different industries. , On the other hand, these resins cause environmental problems due to byproduct release, such as formaldehyde, during their production. Although formaldehyde-free systems do not exhibit the same properties, replacement of formaldehyde with other aldehydes was proposed as a potential solution. , Byproduct release problems of phenolic resins can be alleviated by a reactive monomer strategy . Accordingly, benzoxazines emerged as reactive monomers having 100% atom economy during their ring-opening polymerization (ROP) to produce polybenzoxazines with unique properties. , For example, these polymers can exhibit high thermal stability, glass transition temperatures, mechanical endurance, resistance against flame, low water absorption, dielectric constants, and near-zero volume change during production ,− Another appealing aspect of polybenzoxazines is the easiness of their monomer synthesis.…”