A bio‐based thermoset resin has been synthesized from glycerol reacted with lactic acid oligomers of three different chain lengths (n): 3, 7, and 10. Lactic acid was first reacted with glycerol by direct condensation and the resulting branched molecule was then end‐functionalized with methacrylic anhydride. The resins were characterized by Fourier‐transform infrared spectroscopy (FT‐IR), by 13C‐NMR spectroscopy to confirm the chemical structure of the resin, and by differential scanning calorimetry and dynamic mechanical thermal analysis (DMTA) to obtain the thermal properties. The resin flow viscosities were also measured using a rheometer with different stress levels for each temperature used, as this is an important characteristic of resins that are intended to be used as a matrix in composite applications. The resin with a chain length of three had better mechanical, thermal, and rheological properties than the resins with chain lengths of seven and 10. Also, its bio‐based content of 78% and glass transition temperature of 97°C makes this resin comparable to commercial unsaturated polyester resins. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40488.

A set of novel bio-based star-shaped thermoset resins was synthesized via ring-opening polymerization of lactide and employing different multi-hydroxyl core molecules, including ethylene glycol, glycerol, and erythritol. The branches were endfunctionalized with methacrylic anhydride. The effect of the core molecule on the melt viscosity, the curing behavior of the thermosets and also, the thermomechanical properties of the cured resins were investigated. Resins were characterized by Fourier-transform infrared spectroscopy, 13 C-NMR, and 1 H-NMR to confirm the chemical structure. Rheological analysis and differential scanning calorimetry analysis were performed to obtain the melt viscosity and the curing behavior of the studied star-shaped resins. Thermomechanical properties of the cured resins were also measured by dynamic mechanical analysis. The erythritol-based resin had superior thermomechanical properties compared to the other resins and also, lower melt viscosity compared to the glycerol-based resin. These are of desired characteristics for a resin, intended to be used as a matrix for the structural composites. Thermomechanical properties of the cured resins were also compared to a commercial unsaturated polyester resin and the experimental results indicated that erythritol-based resin with 82% bio-based content has superior thermomechanical properties, compared to the commercial polyester resin. Results of this study indicated that although core molecule with higher number of hydroxyl groups results in resins with better thermomechanical properties, number of hydroxyl groups is not the only governing factor for average molecular weight and melt viscosity of the uncured S-LA resins.

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This work reports an effective self-intumescent flame retardant system for epoxy resin (EP) based on the remarkable synergistic effect between Cu 2 O and ammonium polyphosphate (APP). The effect of Cu 2 O/APP on improving EP's fire performance was evaluated by limited oxygen index (LOI), UL-94, and cone calorimeter test. The optimal mass ratio of Cu 2 O: APP was shown to be 2:8. With 15 wt% total flame retardant loading, the EP with optimum Cu 2 O/ APP formulation reached V-0 classification and high LOI (33.5%), while the EP with APP only got NR and low LOI (26.5%). Additionally, the pHRR, total heat release, total smoke production, CO production of the EP with optimum Cu 2 O/APP formulation were primarily decreased. All the improvements were ascribed to the formation of the self-intumescent char layer of EP resulted from the catalyzing effect of Cu 2 O for char formation and CO to CO 2 conversion. These findings will consolidate approaches for conferring flame retardancy to flammable polymers or their blends.

Regenerated cellulose fibers were used to produce thermoset composites from a bio-based thermoset resin synthesized from lactic acid and glycerol. The resin was impregnated into the regenerated cellulose fiber and compression molded at elevated temperature to produce thermoset composites. Different fiber alignments (unidirectional and bidirectional), different reinforcement type (warpknitted and non-woven) and varying fiber loading (65, 70 and 75 wt%) were investigated. The composites were characterized by flexural, tensile and Charpy impact testing and by dynamical mechanical thermal analysis. Water uptake and ageing properties in climate chamber were also characterized for the composites. The results showed that the composites had good mechanical properties. They can be produced with up to 70 wt% fiber content when using unidirectional (UD) and bidirectional fiber (BD) alignment, and with up to 65 wt% fiber content when using the non-woven (NW) reinforcement. The tensile modulus ranged between 11 and 14 GPa for UD composites, 7 and 8.5 GPa for BD composites and 5 and 7.5 GPa for NW composites. The flexural modulus ranged between 10 and 11.5 GPa for UD composites, 5 and 6.5 GPa for BD composites and 5 and 6 GPa for NW composites. The impact strength ranged between 130 and 150 kJ/m 2 for UD composites, 98 and 110 kJ/m 2 for BD composites and 17 and 20 kJ/m 2 for NW composites. The result of the ageing test showed that the mechanical properties of the composites deteriorate with ageing but the addition of styrene somewhat counteracts the degradation, making the composite applicable for indoor use.

Star‐shaped bio‐based resins were synthesized by direct condensation of lactic acid (LA) with xylitol followed by end‐functionalizing of branches by methacrylic anhydride with three different LA chain lengths (3, 5 and 7). The thermomechanical and structural properties of the resins were characterized by 13C NMR, Fourier transform IR spectroscopy, rheometry, DSC, dynamic mechanical analysis (DMA), TGA and flexural and tensile tests. An evaluation of the effect of chain length on the synthesized resins showed that the resin with five LAs exhibited the most favorable thermomechanical properties. Also, the resin's glass transition temperature (103 °C) was substantially higher than that of the thermoplast PLA (ca 55 °C). The resin had low viscosity at its processing temperature (80 °C). The compatibility of the resin with natural fibers was investigated for biocomposite manufacturing. Finally, composites were produced from the n5‐resin (80 wt% fiber content) using jute fiber. The thermomechanical and morphological properties of the biocomposites were compared with jute‐PLA composites and a hybrid composite made of the impregnated jute fibers with n5 resin and PLA. SEM and DMA showed that the n5‐jute composites had better mechanical properties than the other composites produced. Inexpensive monomers, good thermomechanical properties and good processability of the n5 resin make the resin comparable with commercial unsaturated polyester resins. © 2017 Society of Chemical Industry

38Due to the adverse effects of fossil fuel use, it is becoming increasingly important to 39 produce next-generation biofuels from renewable, sustainable sources. Filamentous N 2 -fixing 40 strains of cyanobacteria have emerged as promising industrial microorganisms capable of 41 producing a range biofuels and chemicals using CO 2 , water, and sunlight. In this study, a life 42 cycle analysis (LCA) was conducted on a hypothetical production facility that uses a genetically 43 engineered strain of filamentous cyanobacteria to produce the cyclic hydrocarbon limonene. Two 44 scenarios were evaluated in which the only difference between the scenarios was the limonene 45 productivity by the engineered cyanobacteria strain. In Scenario 1, the cyanobacterium was 46 assumed to produce limonene at a rate of 1.8 mg/L/h, resulting in an annual production of 32,727 47 L/yr of limonene. In Scenario 2, limonene productivity was 55.5 mg/L/h, resulting in annual 48 production of 1,000,000 L/yr. Both scenarios were assumed to produce the same amount of 49 cellular biomass, that was converted to biogas by anaerobic digestion and the biogas was 50 3 converted by gas turbines into electricity to power the facility. Excess electricity was assumed to 51 be sold to the grid. The major environmental burdens of the facility, which were measured in 52 eco-points and calculated based on the Eco-indicator 99 method, were the cyanobacteria nutrient 53 supply (especially sodium nitrate) and the photobioreactor (PBR) electrical requirements. The 54 lower output of limonene in Scenario 1 meant that less energy was required for product recovery, 55 leaving more electricity for sale to the grid. Even though a higher limonene productivity will 56 worsen the environmental profile of the process, both scenarios described in this study have less 57 of a negative environmental impact than biodiesel production. This study strongly suggests that 58 both scenarios of the theoretical limonene production facility described herein holds great 59 potential as a future sustainable solution for producing next-generation biofuels directly from 60 solar energy. 61 62 Keywords 63 Farm-level algae risk model; Filamentous cyanobacteria; Life-cycle analysis; Limonene; Next-64 generation biofuel 65 66

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