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1.
In this study, bio-thermoset from epoxidized soybean oil (ESO) was prepared in the presence of methylhexahydrophthalic anhydride curing agent and 2-ethyl-4-methylimidazole catalyst. The crosslink densities of the synthesized ESO are ranged from 0.109 × 10?3 to 0.308 × 10?3 mol/cm3. The ESO bio-thermosets were exposed to the soil-burial test for 8 months. Weight change and morphology of the degraded ESO specimens were assessed. It was found that the weight loss of ESO was governed by the materials compositions, crosslink density and the soil-burial exposure time. The 3 mm thickness ESO bio-thermosets with crosslink density of 0.109 × 10?3 mol/cm3 had fully biodegraded after soil-burial for 6 months. In addition, 16S rDNA sequencing was carried out to identify the soil microorganisms. It was suggested that Comamonas sp., Bacillus sp., Streptomyces sp. and Acinetobacter sp. are the possible soil microbes that degrade the ESO bio-thermosets in the compost soil environment.  相似文献   

2.
Polyurethane (PUR) plastic sheets were prepared by reacting hydroxylated polymeric soybean oil (PSbOH) synthesized from autoxidized soybean oil with polyethylene glycol (PEG) in the presence of isophorone diisocyanate (IPDI). FTIR technique was used to identify of chemical reactions. These polyurethanes have different valuable properties, determined by their chemical composition. The effect of stoichiometric balance (i.e., PSbOH/PEG-2000/IPDI weight ratio) on the final properties was evaluated. The polyurethane plastic sheets with the PSbOH/PEG-2000/IPDI weight ratio 1.0/1.0/0.67 and 1.0/0.3/0.3 had excellent mechanical properties indicating elongation at break more than 200%. Increase in IPDI and decrease in PEG weight ratio cause the higher stress–strain value. The properties of the materials were measured by differential scanning calorimetry (DSC), thermo gravimetric analysis (TGA), stress–strain measurements and FTIR technique.  相似文献   

3.
Journal of Polymers and the Environment - The bio-based acoustic materials have flourished with the future depletion of petroleum resources in recent years. This paper dedicates on the synthesis of...  相似文献   

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Novel renewable polyols based on limonene were synthesized using thiol-ene “click” chemistry. These limonene based polyols were structurally characterized using wet methods (hydroxyl number, acid value and viscosity), gel permeation chromatography and spectroscopic methods. The results indicated that high yield of polyols from limonene based materials can be obtained using thiol-ene reaction. These limonene based polyols were used successfully for preparation of rigid polyurethane foams. These foams had regular shape cells and uniform cell size distribution. Thermal studies on these foams indicated that foams were thermally stable up to 250 °C. The glass transition temperature of the foams was higher than 200 °C. These rigid polyurethane foams had high compressive strength and the highest compressive strength of 195 kPa was observed. These foams have good physical–mechanical characteristics and could be suitable for all the applications of rigid polyurethane foams such as thermal insulation of freezers, storage tanks for the chemical and food industries, and packing materials for food industries.  相似文献   

6.
Biobased polyols were synthesized from rapeseed oil (RO) with diethanolamine (DEA), triethanolamine (TEA) and glycerol (GL) at different molar ratios. The structures of the synthesized polyols were analyzed using FTIR-ATR spectroscopy. Polyurethane (PU) networks from RO/DEA polyols and polymeric MDI showed higher tensile strength, modulus and hardness, but their elongation at break decreased, compared to the case of the PU obtained from RO/TEA and RO/GL polyols. The tensile strength and modulus of PU networks increased with increasing PU cohesion energy density (CED) and decreasing molecular weight between crosslinks M c . From the thermogravimetric analysis and its derivative thermograms, at the first stage of destruction (below 5 % weight loss) in the air and inert atmosphere, the PU obtained from RO polyols were ranked in the following order: PU RO/GL > PU RO/TEA > PU RO/DEA, and their thermostability was higher than that of the PU based on propylene oxide.  相似文献   

7.
Polyurethane foam (PUF) was prepared from liquefied wood with polymethylene polyphenylisocyanate by one-shot method, with organosilicon as surfactant, water as blowing agent and stannous octoate and triethylene diamine as co-catalyst. The biodegradability of the PUF was studied by soil burial for a period of 12 months. The Fourier transform infrared (FT-IR) study, morphological observation and percent weight loss were used to discuss the biodegradability of polyurethane foam from liquefied wood. The FT-IR analyses showed that the PUF had biodegraded via oxidation of the ether soft segment or degradation of wood components. The weight loss rate showed that the addition of liquefied wood could accelerate the degradation of PUF.  相似文献   

8.
Journal of Polymers and the Environment - Biodegradable materials provide a primary function in preserving and protecting food products, helping to extend shelf life. The present work aims to...  相似文献   

9.
Castor oil was chemically modified into a diethanolamide by a two step process. The first step was the hydroxylation of double bonds in castor oil and second step was the transamidation using diethanolamine to increase the hydroxyl value. Water blown polyurethane foams were developed with this castor oil based polyol using polypropylene glycol of molecular weight 1,000 as the copolyol and polymeric MDI. The density and mechanical properties namely compression and flexural strength depended on the composition of the foam formulation. The hydroxyamide content and molecular weight of commercial polyol had significant effect on the micro structure as observed by optical microscopy.  相似文献   

10.
Journal of Polymers and the Environment - The study investigated the effect of lignocellulosic biomass filler decayed by brown-rot fungi on the preparation and properties of polyurethane (PU) foam....  相似文献   

11.
Epoxy resin prepared by the reaction of a diglycidyl ether of bisphenol A (DGEBA) and m-xylylenediamine (m-XDA) was modified with 10% wt of epoxidized palm oil (EPO). The EPO was first pre-polymerized with m-XDA at various temperatures and reaction times. The resulting product was then mixed with the epoxy resin at 40?°C and allowed to react at 120?°C for another 3?h. The fully reacted DGEBA/m-XDA/EPO blend was characterized by using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermal gravimetric analysis, tensile test, hardness indentation and dynamic mechanical analysis. The SEM study shows that different types of morphology, ranging from phase separated to miscible blends were obtained. A miscible blend was obtained when the m-XDA and EPO were reacted for more than 2?h. The results from DSC analysis show that the incorporation of EPO at 10% wt in the epoxy blend reduced the glass transition temperature (T g). The lowered T g and mechanical properties of the modified epoxy resins are caused by a reduction in crosslinking density and plasticizer effect.  相似文献   

12.
The waterborne polyurethane (PU) prepolymer was prepared based on isophorone diisocyanate (IPDI), polyester polyol (N220), dimethylol propionic acid (DMPA) and hydroxyethyl methyl acrylate (HEMA). The modified waterborne polyurethane–acrylate (PUA) emulsions were obtained with different proportions of acrylate (butyl acrylate and methyl methacrylate) and initiating agent by in situ dispersion technique. The structures and thermal properties of prepared PU and PUA were analyzed and characterized with FT-IR, UV–Vis spectroscopy and DSC. The PUA hybrid samples had lower glass transition temperature of hard segment and higher decomposition temperatures than PU sample. Performances of the emulsion and film were studied by means of apparent viscidity, particle size and polydispersity, surface tension and mechanical properties. The results indicated that the particle sizes of the PUA dispersions were larger than those of the pure PU and the solvent resistance, mechanical properties of PUA films was improved compare with the unmodified polyurethane film. The film had the biggest hardness and the least water absorption when the BA/MMA mass ratio 5:5 modified PU. The obtained PUA have great potential application such as coatings, leather finishing, adhesives, sealants, plastic coatings and wood finishes.  相似文献   

13.
Journal of Polymers and the Environment - This study aims to improve low intrinsic ductility of poly (lactic acid) (PLA) by using a novel bio-sourced plasticizer environmentally friendly and...  相似文献   

14.
Journal of Polymers and the Environment - Biocomposites based on polyethylene from renewable resources derived from sugar cane as raw material were modified with phosphonium ionic liquids....  相似文献   

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Novel polymer blends based on completely renewable polymers were reported. Polymer blends based on polylactic acid (PLA) and oxidized and hydroxylated soya bean oil polymers were prepared. Plasticization and mechanical strength effect of the soya bean oil polymers on the PLA were observed. Fracture surface analysis of the polymer blends was carried out by using scanning electron microscopy. The PLA blends showed more amorphous morphologies compared to pure PLA. The blends had better elongation at break in view of the stress–strain measurement. Blend of PLA with the hydroxylated polymeric soya bean oil indicated the slightly antibacterial properties.  相似文献   

17.
In the present investigation, microfibrils were extracted from raw bamboo and characterized using scanning electron microscope. Composites based on polyhydroxybutyrate (PHB) and bamboo microfibril were prepared with various microfibril loading. The mechanical and thermal properties of the resulting composites were measured. Tensile strength and impact strength of the composites were found to be increasing with increase in the loading of bamboo microfibrils, reached an optimum and thereafter decreased with further increase in microfibril loading. Percentage crystallinity was found to be increasing with increase in fibril loading. Thermal stability of the composite was higher than that of pure PHB. The composite could be developed further for various structural applications.  相似文献   

18.
Journal of Polymers and the Environment - The influence of alkaline treatment on the thermal and mechanical properties of polypropylene (PP) reinforced with fibers from macadamia nutshell (5 to 30...  相似文献   

19.
Organically modified montmorillonite clays were incorporated at a 5% loading level into film grade of poly-L-lactic acid (PLLA) using a variety of masterbatches based on either semi-crystalline or amorphous poly-(lactic acid), as well as biodegradable aromatic aliphatic polyester. The PLLA masterbatches and compounded formulations were prepared using a twin screw compounding extruder, while the films were prepared using a single screw cast film extruder. The thermal and mechanical properties of the films were examined in order to determine the effect of the clay and different carriers on the polymer–clay interactions. In the optimal case, when a PLLA-based masterbatch was used, the tensile modulus increased by 30%, elongation increased by 40%, and the cold crystallization temperature decreased by 15 °C, compared to neat PLLA. The properties improvement of PLLA films containing nano clays demonstrated the possibility to extend the range of biodegradable film applications, especially in the field of packaging.  相似文献   

20.
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