Crosslinking network of bio‐based bis‐functional epoxides derived from trans‐limonene oxide

Abstract

The thiol‐ene reaction between trans‐limonene oxide (trans‐LO) and ethane‐1,2‐dithiol in the presence of triethylborane affords a bio‐based bis‐functional epoxide (bis‐trans‐LO). The crosslinking reaction of bis‐trans‐LO with branched polyethyleneimine (BPEI; Mn = 600; BPEI600) at a feed ratio of bis‐trans‐LO/BPEI600 = 57/43 (wt/wt) yields the corresponding network polymer with Td10 (10% thermal decomposition temperature) of 304.7 °C in 98% yield. In contrast, negligible amounts of network polymer are obtained by the reaction of bis‐LO (bis‐functional epoxide derived from cis and trans‐LO) and BPEI600 regardless of the feed ratio. The mechanical strengths as measured by direct tensile tests of the network polymers derived from bis‐trans‐LO and BPEI600,1800 (Mn = 600 and 1800) were approximately 16 and 11 times higher than that of bis‐LO and BPEI1800, respectively. The tensile shear strengths of the metal‐to‐metal adhesive bonds induced by bis‐trans‐LO and BPEI600,1800 were 9.5 and 14.1 MPa, respectively. DMA revealed that the storage modulus of the network polymer derived from bis‐trans‐LO and BPEI1800 in the rubber region was higher than that of the material prepared from bis‐LO and BPEI1800, indicating higher crosslink density of the bis‐trans‐LO/BPEI1800 system. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2466–2473

Synthesis of a Curing Agent Derived from Limonene and the Study of Its Performance to Polymerize a Biobased Epoxy Resin Using the Epoxy/Thiol-Ene Photopolymerization Technique

“…Limonene is a low-cost and readily available terpene with a variety of applications in different areas such as food and beverages [ 19 , 20 ], pharmaceutical [ 21 ], bio-solvent [ 22 ], cosmetics and personal care [ 23 , 24 ]. Limonene has also been used as a building block to prepare various types of biobased polymers [ 25 , 26 , 27 , 28 ]. This terpene is obtained from distillation or by solvent extraction from the peels of citrus fruits.…”

Use of Limonene Epoxides and Derivatives as Promising Monomers for Biobased Polymers

“…The corresponding network polymer showed high thermal decomposition temperature ( T d10% ∼305 °C), tensile strength up to 2.2 MPa (while the tensile strength of bis‐LO network was 0.2 MPa). The storage modulus of bis‐ trans ‐LO/BPEI system was also 4 times higher than that of bis‐LO/BPEI, indicating a higher crosslink density [31] . Those results are promising but still need improvements to compete with common commercially available epoxy polymers.…”

Trans‐limonenedioxide, a promisingbio‐basedepoxy monomer

“…Glycidyl esters of rosin acid oligomers have been cross‐linked with isophorone diamine and shown to lead to epoxy polymers with comparable properties to those obtained with BADGE 14 . Limonene Oxide (LO) has been dimerized with various dithiol compounds via a thiol‐ene reaction, and the resulting products have also been used as epoxy monomer 15–17 . The recent report that limonene can be catalytically epoxidized using oxygen 18 sparked our interest for the use of limonene dioxide (LDO) as biosourced epoxy monomer (Figure 1).…”

“…14 Limonene Oxide (LO) has been dimerized with various dithiol compounds via a thiol-ene reaction, and the resulting products have also been used as epoxy monomer. [15][16][17] The recent report that limonene can be catalytically epoxidized using oxygen 18 sparked our interest for the use of limonene dioxide (LDO) as biosourced epoxy monomer (Figure 1).…”