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Developing a feasible and low-cost approach to fabricate recyclable, UV-shielding, biodegradable as well as water- and oil-resistant coating for paper substance is still a challenge. Herein, novel full-biobased chitosan-derived cardanol glycidyl ether (CS-xCGE, x = 1/8, 1/4, 1/2, and 1) coatings with different contents of cardanol glycidyl ether (CGE) were developed for paper substance via the ethoxylation of cardanol and sequent addition with chitosan in a one-pot process. Benefiting from the hydrophobicity and ultraviolet resistance of CGE, the resultant CS-CGE (x = 1) coated paper exhibited not only remarkable oil resistance (kit rating value of 11/12), but also water resistance (Cobb 60 value of 5.78 g/m

Paper derived from lignocellulose has great advantages over plastics as packaging material, nevertheless, the poor water- and oil-resistances of paper-derived products limited their application in high-end field. Herein, novel dimer acid-based waterborne polyurethanes (DWPUs) with different content of dimer acid-based polyester polyol (DG) were prepared and used as water- and oil-resistant coating for paper substrate. The effects of DG contents on water- and oil-resistances, mechanical properties and thermal stability of DWPUs coated papers were systematically investigated. When the content of DG reached up to 7 wt% (based on polyester glycol), the paper coated by DWPU exhibited 88.06% decrease in Cobb 60 value, 8.7 times increase in kit rating compared with uncoated paper. Meanwhile, DWPUs coated papers showed good mechanical properties and thermal stability. These improvements are attributed to the flexible long-alkyl chain, and six-ring structure of DWPUs as well as the continuous and homogeneous DWPU-derived membrane on the surface of paper. This study provides a new framework for the preparation of high quality, multifunctional, environmentally friendly water- and oil-resistant coatings for paper substrates.

Poly(lactic acid) (PLA) is a green but brittle thermoplastic, and its flexibility must be improved to meet the requirements of application. In this work, a series of waste frying oil-derived esters...

In this work, a series of novel bio-based plasticizers, including ethoxylated esters, methylated esters, and glycidyl esters, originated from waste frying oil (WFO), were prepared, characterized, and used as primary plasticizers for Poly (vinyl chloride) (PVC). The glass transition temperature, mechanical properties, transparency, UV resistance, thermal stability and migration resistance of plasticized PVC were investigated and compared with that of the PVC sample plasticized by the commercial dioctyl terephthalate (DOTP). It is found that all of those properties are significantly depended on the structures of ester groups. In particular, the esters bearing ethyoxyl units show better plasticization than that having methyl or glycidyl groups. In addition, the plasticizing efficiencies of WFO-derived ethoxylated esters are proportional to the number of ethyoxyl units in their structures. Among them, the anti-ultraviolet PVC sample plasticized by WFO-derived polyacid (triethylene glycol monomethyl ether) esters (WFOPA-3, “3” refers to the number of ethylene glycerol units in the feedstock of triethylene glycol monomethyl ether) with maximum ethyoxyl units exhibited the best plasticization, thermal stability, and transparency than the properties of other samples plasticized by WFO-based plasticizers, as well as petro-based DOTP. The results suggest WFOPA-3 is an attractive potential as alternative to DOTP.

To reduce crude oil consumption and the corresponding environmental impact, the use of sustainable resources has recently attracted much attention. Herein, a low-viscosity and efficient tannin-based epoxy resin (MTEBPE) was prepared using liquefaction of renewable tannin (MTEBP) and epichlorohydrin feedstocks, and then used as modifier to enhance the toughness and strength of fossil fuel-based bisphenol A diglycidyl ether (DGEBA). The results show that the mechanical properties of the thermosets could be significantly improved after blending with MTEBPE; in particular, the tensile, flexural, and impact strengths, as well as the elongation at break of 5 wt% MTEBPE/DGEBA increased by 35.8%, 45.4%, 243.8%, and 81.6%, respectively, compared with those of neat DGEBA. The enhanced toughness and strength of the epoxy thermosets can be attributed to the combined effect of the crosslinking density, intramolecular cavities, and branched structure of MTEBPE. More importantly, the temperatures corresponding to 5% and 50% weight loss (T5% and T50%, respectively) and the char yield at 600 °C of the 5 wt% MTEBPE/DGEBA thermosets were basically the same as those of neat DGEBA. In addition, the thermosets exhibited excellent chemical resistance, also to alkali and organic solvents. In brief, MTEBPE, a multifunctional bio-based epoxy derived from waste bark, shows great application advantages in coatings, adhesives, and functional materials.

A series of supported alkali metal salts were investigated as catalysts to produce propylene oxide (PO) from biomass-derived 1,2-propanediol via dehydrative epoxidation in a solid–gas reaction system. The effects of supports, cations, and anions in the alkali metal salts and calcination temperature were investigated by X-ray diffraction and CO2-temperature-programmed desorption. The results indicate the catalysts with relative mild basicity having higher yields of PO. The highest yield of PO is 58.2% from reactions at 400 °C at an atmospheric pressure over KNO3/SiO2. In addition, the catalyst could be reused after calcination in air at 550 °C.

In this work, dimer acid diglycidyl ester (DAGE) was synthesized from the dimer acid via a two-step method and applied as a bio-based toughener for bisphenol A epoxy resin (DGEBA). Mechanical tests demonstrated that DAGE had significant effects on the flexibility of DGEBA. When 5 wt% DAGE was incorporated into DGEBA system, there was an enhancement of 2.56 times of the impact strength. Meanwhile, the tensile strength and elongation at break increased by 17.2 % and 13.4 %, respectively. In addition, the curing behavior of DAGE/DGEBA system was kinetically modeled based on non-isothermal DSC data. The incorporation of DAGE has little effect on the apparent activation energy of the system. Moreover, the curing process can be accurately described by the Sestak-Berggren model. The bio-derived DAGE holds great potential for practical applications.

Direct transformation of monomer fatty acids derived from the dimer acid manufacturing into high value-added green plasticizers represents a sustainable approach for reutilizing industrial wastes. However, this process is challenging due to the few double bonds and long-chain alkyl in monomer fatty acid-based derivatives, resulting in poor compatibility with polymer matrix and inferior plasticization. Herein, we develop a sustainable and low-cost strategy via direct esterification between monomer fatty acids and polyethylene glycol methyl ether to produce plasticizers featured by high plasticization and compatibilization. The performances of monomer acid-based ethoxylated esters as resulting plasticizers for nitrile butadiene rubber were highly structure-dependent. Extensive experiments demonstrated that oxethyl unit played critical roles in both improving the compatibility between monomer acid-based ethoxylated esters and nitrile butadiene rubber and in promoting the dispersion of carbon black in nitrile butadiene rubber matrix. Specially, the processing, freezing resistance, oil resistance, thermal and mechanical stabilities of nitrile butadiene rubber plasticized by monomer acid-based ethoxylated esters with three or four oxethyl units were comparable or better than those of nitrile butadiene rubber blended with dioctyl phthalate. This study opens a simple, general and industrialized strategy to produce valuable and sustainable plasticizers as alternatives of toxic dioctyl phthalate.

A series of new environment-friendly plasticizers was synthesized from castor oil and used to plasticize nitrile rubber (NBR). The test results showed that tensile strength, elongation at break, and tear strength of NBR vulcanizates plasticized by castor oil-based plasticizers were found to be better than that of dioctyl phthalate (DOP). The aging test taken demonstrated that the castor oil-based plasticizers could improve the hot air and oil aging resistance of NBR vulcanizates. The thermal stability test illustrated that castor oil-based plasticizers enhanced the thermal stability of NBR vulcanizates, and the initial decomposition temperatures (T10%) were about 100 &deg, C higher than that of DOP. In general, the studies manifested that EACO and EBCO can replace DOP to plasticize NBR and are used in fields that require high mechanical properties, aging resistance, and thermal stability. This study emphasizes the effects of sustainable, cost-effective, and high-efficiency plasticizers on NBR.

Developing vegetable oil-derived primary plasticizers for poly(vinyl chloride) (PVC) is still a challenge because of their insufficient compatibility. As described in this work, we report the synthesis of plasticizers through the esterification of polyethylene glycol methyl ether and dimer acid, in which dimer acid is renewable material prepared via a two-step reaction (1) the hydrolysis of fatty acids from soybean oil at 70 &deg, C and (2) subsequent Diels&ndash, Alder reaction at 250 &deg, C. The resulting plasticizers, dimer acid-derived polyethylene glycol methyl ether esters (DA-2n, 2n = 2, 4, 6 or 8 referring to the number of oxethyl units per molecule), were blended with PVC. It was found that the tensile properties, transparency, and thermal stability of plasticized PVC (PVC-DA-2n) increased significantly with an increase in the number of oxyethyl units. Fourier-transform infrared spectroscopy analysis revealed that its good compatibility can be attributed to the strong interaction between oxyethyl units and PVC. As the number of the oxyethyl units of plasticizer increased, the glass transition temperature (Tg) of the corresponding plasticized PVC samples decreased from 62.3 (PVC-DA-2) to 35.4 &deg, C (PVC-DA-8). Owing to the excellent plasticization of DA-8, the performances of PVC-DA-8 were comparable or better than that of the PVC plasticized using commercial dioctyl terephthalate (DOTP). The simple but efficient method of this study provides a new avenue for the preparation of vegetable oil-based plasticizers for PVC.