A high toughness elastomer based on naturalEucommia ulmoidesgum

Abstract

Eucommia ulmoides gum (EUG) is a kind of bio-based polymer with similar structure to natural rubber (NR). However, it behaves as hard plastic at room temperature due to crystallization, which makes it not as widely used as NR. Herein, a new bio-based elastomer (HEUG) was prepared by rhodiumcatalyzed hydrogenation of EUG for the first time. 1 H-NMR and 13 C-NMR spectroscopy confirmed the structure of HEUG, and wide angle X-ray diffraction, polarizing light microscopy showed that the crystal was gradually destroyed in the hydrogenation process, finding that when the degree of hydrogenation is more than 16.5%, HEUG transformed from plastic to elastomer at room temperature. Besides, the Synchrotron Radiation experiment showed that HEUG with hydrogenation of 85.9% could be self-reinforced by strain-induced crystallization during stretching, which make it has excellent tensile strength and toughness (21.4 MPa and 68.1 MJ m −3 , respectively). This new bio-based elastomer has the potential to replace NR and has a wide application prospect in rubber industry.

Covalent crosslinks turn natural Eucommia ulmoides gum/polybutene‐1 composites into multiple shape memory materials

“…50°C can be ascribed to the EUG portion. [ 16,38 ] With increasing DCP content, the melting temperature (T m ) and relative crystalline degree (χ c ) of both EUG and PB‐1 components tended to decrease as can be seen from Table 3. This is understandable considering the fact that the mobility of EUG and PB‐1 molecules was abated due to strong restriction from the covalent crosslinks, which led to poor capacity of changing their conformations.…”

Current trends in bio‐based elastomer materials

“…Reproduced with permission: Copyright 2013, Elsevier 100 of 400% for an HEUG with 85.9% of hydrogenation. 104 To date, efforts are being made to expand the application field of EUG. 32,[103][104][105][106][107][108][109][110] It is used in tires 111,112 , damping materials, 108,113,114 and shape-memory materials.…”

“…104 To date, efforts are being made to expand the application field of EUG. 32,[103][104][105][106][107][108][109][110] It is used in tires 111,112 , damping materials, 108,113,114 and shape-memory materials. [115][116][117][118][119] For example, partially bio-based TPVs are obtained by in situ dynamic vulcanization of EUG and polyolefin elastomer and show good shape memory performances with a shape F I G U R E 7 A pilot plant demonstrator for extracting dandelion rubber with an annual capacity of 100 tons.…”

Achieving high elasticity of trans-1,4-polyisoprene with a combination of radiation crosslinking and thiol–ene grafting

“…5 To this end, the crystallization of TPI has to be suppressed. Modification of TPI includes chlorination, [6][7][8] hydrogenation, 9 epoxidation, [10][11][12] grafting, 13,14 and Alder-ene reaction. 15,16 These methods modify the chemical structure of a certain number of monomers in the TPI chains, which act as defects for crystallization.…”