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In the scope of fully bio-based materials development, access to bio-based aromatic amine monomers is one of the main industrial challenges over the coming years. In this paper, new bio-based amine monomers derived from vanillin were prepared by the direct amination of an epoxy monomer with aqueous ammonia. These synthesized amines exhibited high reactivity due to the presence of secondary OH groups. Then these amines were added to epoxies to form thermosets by a cross-linking reaction. After curing, the thermal and mechanical behaviors of the synthesized networks were determined and compared to that of a petroleum-based reference system with DGEBA as an epoxy. [ABSTRACT FROM AUTHOR]

Abstract: The alkylation of alcohols and polyols has been investigated with alkylphosphates in the presence of a Lewis or Brønsted acid catalyst. The permethylation of polyols was developed under solvent‐free conditions at 100 °C with either iron triflate or Aquivion PW98, affording the isolated products in yields between 52 and 95 %. The methodology was also adjusted to carry out peralkylation with longer alkyl chains. [ABSTRACT FROM AUTHOR]

Two methods for the preparation of 5-iodo-1,2,3-triazolyl-4-phosphonate were explored. This compound was then functionalized by Suzuki and Stille cross-coupling reaction to obtain 5-aryl-, 5-heteroaryl- or 5-alkenyl-1,2,3-triazolyl-4-phosphonates. [ABSTRACT FROM AUTHOR]

Most of the current amine hardeners are petro-sourced and only a few studies have focused on the research of bio-based substitutes. Hence, in an eco-friendly context, our team proposed the design of bio-based amine monomers with aromatic structures. This work described the use of the reductive amination with imine intermediate in order to obtain bio-based pluri-functional amines exhibiting low viscosity. The effect of the nature of initial aldehyde reactant on the hardener properties was studied, as well as the reaction conditions. Then, these pluri-functional amines were added to petro-sourced (diglycidyl ether of bisphenol A, DGEBA) or bio-based (diglycidyl ether of vanillin alcohol, DGEVA) epoxy monomers to form thermosets by step growth polymerization. Due to their low viscosity, the epoxy-amine mixtures were easily homogenized and cured more rapidly compared to the use of more viscous hardeners (<0.6 Pa s at 22 °C). After curing, the thermo-mechanical properties of the epoxy thermosets were determined and compared. The isophthalatetetramine (IPTA) hardener, with a higher number of amine active H, led to thermosets with higher thermo-mechanical properties (glass transition temperatures (Tg and Tα) were around 95 °C for DGEBA-based thermosets against 60 °C for DGEVA-based thermosets) than materials from benzylamine (BDA) or furfurylamine (FDA) that contained less active hydrogens (Tg and Tα around 77 °C for DGEBA-based thermosets and Tg and Tα around 45 °C for DGEVA-based thermosets). By comparing to industrial hardener references, IPTA possesses six active hydrogens which obtain high cross-linked systems, similar to industrial references, and longer molecular length due to the presence of two alkyl chains, leading respectively to high mechanical strength with lower Tg. [ABSTRACT FROM AUTHOR]

In this paper, epoxy‐anhydride networks are synthesized from a new product of Cardolite Corporation: the Cardolite GX‐2551 epoxy monomer. Due to the complexity of the GX‐2551 structure, an NMR study is performed first to characterize this new commercial product. This epoxy monomer is then reacted with an anhydride (MHHPA) to form polyepoxide thermosets. After curing, dynamic mechanical and thermal analyses are performed for the different thermosets, and then the results are compared to each other. Practical Applications: The cardanol‐derived epoxy monomer described in this contribution, i.e., fully epoxidized molecular cardanol, is a new fully biobased monomer for further epoxy thermoset synthesis. The resulting polyepoxide networks exhibit much higher thermo‐mechanical properties than previous cardanol‐derived epoxy thermosets. Two cardanol‐based epoxy monomers are fully characterized. The GX2551 is reported for the first time and exhibits a higher renewable carbon content. Both monomers are reacted with hexahydro‐4‐methylphtalic anhydride to yield bio‐based aromatic polyepoxide networks with interesting mechanical and thermal properties. [ABSTRACT FROM AUTHOR]