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1.
Wei Seng Ng Choy Sin Lee Sit-Foon Cheng Cheng Hock Chuah Shew Fung Wong 《Journal of Polymers and the Environment》2018,26(7):2881-2900
Biodegradable polyester polyol was synthesized from oleochemical glycerol monostearate (GMS) and glutaric acid under a non-catalyzed and solvent-free polycondensation method. The chemical structure of GMS-derived polyester polyol (GPP) was elucidated by FTIR, 1H and 13C NMR, and molecular weight of GPP was characterized by GPC. The synthesized GPP with acid value of 3.03 mg KOH/g sample, hydroxyl value of 115.72 mg KOH/g sample and Mn of 1345 g/mol was incorporated with polyethylene glycol (PEG) and polycaprolactone diol (PCL diol) to produce a water-blown porous polyurethane system via one-shot foaming method. The polyurethanes were optimized by evaluating glycerol as a crosslinker, silicone surfactant and water blowing agent on tensile properties of polyurethanes. All polyurethanes underwent structural change, and crystalline hard segments of polyurethanes were shifted to higher temperature suggested that hard segments undergone re-ordering process during enzymatic treatment. In terms of biocompatibility, polyurethane scaffold produced by reacting 100% w/w of GPP with isophorone diisocyanate and additives showed the highest cells viability of 3T3 mouse fibroblast (94%, day 1), and MG63 human osteosarcoma (107%, day 1) and better cell adhesion as compared to reference polyurethane produced by only PEG and PCL diol (3T3 cell viability: 8%; MG63 cell viability: 2%). The current work demonstrated GPP synthesized from renewable and environmental friendly resources produced polyurethanes that allows improvement in physico-chemical, mechanical and biocompatibility properties. By blending with increasing content of GPP, the water-blown porous polyurethane scaffold has shown great potential as biomaterial for soft and hard tissue engineering. 相似文献
2.
Omar Faruk Mohini Sain Ramin Farnood Yuanfeng Pan Huining Xiao 《Journal of Polymers and the Environment》2014,22(3):279-288
The green rigid polyurethane (PU) foam has been developed with 100 % soy polyol after optimization of formulation ingredients and lignin has been introduced and isocyanate content reduced in the green rigid PU foam. The cellulosic nanofibers have also been successfully incorporated and dispersed in green rigid PU foam to improve the rigidity. The influence of nano cellulose fiber modification (enzymatic treatment, hydrophobic modification with latex) on the foam density, open cell content, foam raise height, water vapor, and mechanical properties of rigid PU foam were studied. The foamed structures were examined using scanning electron microscopy to determine the cell size and shape due to the addition of cellulosic nanofibers. The odor test were performed to evaluate the odor concentration 100 % soyol based PU foam including lignin and nanofiber and compared to 100 % synthetic based polyol PU foam. The experimental results indicated that the compression and impact properties improved due to the modification of nano cellulosic fibers. The odor concentration level of nanofiber reinforced rigid PU foam reduced significantly compared to 100 % PU foam due to the replacing of isocyanate content. It can be said that with an appropriate combination of replacing isocyanate by lignin and addition of nanofiber, rigid PU foam properties could be improved. 相似文献
3.
Effects of Wood Fiber and Microclay on the Performance of Soy Based Polyurethane Foams 总被引:1,自引:0,他引:1
Various polyurethane (PU) foams were prepared by in situ reaction of isocyanate and soy-based polyol. The effects of wood fiber and microclay on the foam morphologies, mechanical properties and thermal behaviors of PU foams were investigated. NCO index had fundamental impacts on the influences of wood fiber and microclay on the performance of PU foams. The reinforcement behavior of flexible foams was different to that of both semi-rigid and rigid foams. Both fiber and microclay improved the compressive strength at a high NCO index of 140–250, and contributed to relative high decomposition temperatures. Unlike the compressive strength, the tensile strength was decreased due to the amount of hard polyurea formation from secondary reactions at the highest NCO level. In addition, wood fiber had different reinforcement mechanism from microclay. Wood fiber desired to form chemical bonds during foaming while microclay had potential to form physical insertions. This difference was expressed by the change of their thermal degradation temperature. 相似文献
4.
Carolina Molero Antonio de Lucas Fernando Romero Juan F. Rodríguez 《Journal of Material Cycles and Waste Management》2009,11(2):130-132
Flexible polyurethane foam wastes can be advantageously treated by two-phase glycolysis to recover the polyols with an improved
quality compared to single-phase processes. This reaction has been traditionally catalyzed by alkanolamines, titanium compounds,
or acetates. Recently, the employment of new catalysts based on potassium and calcium octoates has opened up a new way to
catalyze the glycolysis of polyurethanes. In this work, the use of stannous octoate, which has never before been applied in
the glycolysis reactions of polyurethanes, is proposed. The catalytic activity of stannous octoate in such a process was studied.
The decomposition rate and the purity of polyol obtained were greater than those obtained using other catalysts previously
employed for this application. 相似文献
5.
Thermal and Mechanical Properties of Polyurethane Rigid Foam Based on Epoxidized Soybean Oil 总被引:2,自引:0,他引:2
Li-Ting Yang Cheng-Shan Zhao Chun-Lan Dai Li-Yu Fu Shao-Quan Lin 《Journal of Polymers and the Environment》2012,20(1):230-236
A soypolyol based on epoxidized soybean oil (ESO) was prepared in the presence of HBF4 and diethanolamine (DEA) was used as ring opener. A series of polyurethane rigid foam were prepared by mixing polyol with
TDI using an isocyanate index of 1.1. The polyol used in this paper were a mixture of soypolyol and a commercial PL-5601 polyester
polyol and the mass fraction of PL-5601 was in the range of 0–60%. The thermal properties of the resins were characterized
by DSC and TG. The results showed that these rigid foams possess high thermal stability. There were two glass transition temperature
of each foam and Tg1 was increasing with the increasing of OH value. The compression strength of the foam was also recorded, and the effect of
mass ratio of soypolyol and PL-5601 polyester polyol on the compression strength was discussed. 相似文献
6.
Tadeusz Spychaj Ewa Fabrycy Stanislawa Spychaj Michal Kacperski 《Journal of Material Cycles and Waste Management》2001,3(1):24-31
This paper describes the chemical degradation of waste poly(ethylene terephthalate) (PET) with polyamines or triethanolamine,
the characteristics of the products, and a search for ways to use these products. Solvolysis of the polymer ester bonds was
caused by diethylenetriamine, triethylenetetramine, and their mixtures, as well as mixtures of triethylenetetramine and p-phenylenediamine or triethanolamine. Products of aminolysis or aminoglycolysis of PET obtained in reactions performed at
200–210°C (with a molar ratio of the recurrent polymer unit to amine of 1 : 2) have been characterized using nuclear magnetic
resonance (NMR). Viscosity and hydroxyl number measurements have been done for PET/triethanolamine products. Substances from
aminolytical reactions with polyamines were tested as hardeners for liquid epoxy resins, and the product of polymer aminoglycolysis
with triethanolamine was tested as an epoxy resin hardener, e.g., for water-borne paints, and a polyol component for rigid
polyurethane foams. The compositions of epoxy resin hardeners have been characterized using DSC and rheometry. Comparative
analyses of the hardened epoxy materials have been done on the basis of glass temperature and mechanical properties data,
as well as some specific properties of the coating materials and rigid polyurethane foams.
Received: September 15, 2000 / Accepted: September 21, 2000 相似文献
7.
Mihail Ionescu S. Sinharoy Zoran S. Petrović 《Journal of Polymers and the Environment》2009,17(2):123-130
The synthesis of telechelic polyacetals with terminal hydroxyl groups (polyacetal polyols), by the reaction of triethylene
glycol divinyl ether with dipropylene glycol in the presence of trimethylolpropane or other triols or diols as starters, in
acidic catalysis, has been studied. The synthesized liquid polyacetal triols and polyacetal diols were characterized by hydroxyl
number, viscosity, acidity, number average molecular weight (Mn), weight average molecular weight (Mw), molecular weight distribution (Mw/Mn), FT-IR spectra. The obtained polyacetals were transformed in cast elastomers by the reaction with the isocyanate Mondur
CD (modified diphenyl methane diisocyanate) with properties very close to the elastic polyurethanes obtained by using conventional
polyether triols, copolymers propylene oxide–ethylene oxide. The polyacetal polyols are suitable for the synthesis of elastic
polyurethanes (polyurethane elastomers, flexible polyurethane foams). Polyacetals are well known biodegradable polymers. Therefore,
the polyurethanes based on polyacetal polyols are expected to be biodegradable. 相似文献
8.
Environmentally Friendly Polyurethane Composites: Preparation, Characterization and Mechanical Properties 总被引:1,自引:0,他引:1
J. L. Zhang D. M. Wu D. Y. Yang F. X. Qiu 《Journal of Polymers and the Environment》2010,18(2):128-134
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
9.
This paper describes the effect of the modification of polyurethane system with palm oil-based polyol on the cell structure and physical?Cmechanical properties of polyurethane foams. Flexible polyurethane foams were prepared by substituting a part of petrochemical polyether-polyol with the palm oil polyol. Selected physical?Cmechanical properties of these foams were examined and compared to the properties of reference foam. The properties such as apparent density, tensile strength, elongation at break, resilience, compressive stress and thermal stability were analyzed. It was found that the modifications of polyurethane formulation with palm oil polyol allow to improve selected properties of final products. 相似文献
10.
Aleksander Hejna Paulina Kosmela Mikelis Kirpluks Ugis Cabulis Marek Klein Józef Haponiuk Łukasz Piszczyk 《Journal of Polymers and the Environment》2018,26(5):1854-1868
In this work, rigid polyisocyanurate foams were prepared at partial substitution (0–70 wt%) of commercially available petrochemical polyol, with previously synthesized biopolyol based on crude glycerol and castor oil. Influence of the biopolyol content on morphology, chemical structure, static and dynamic mechanical properties, thermal insulation properties, thermal stability and flammability was investigated. Incorporation of 35 wt% of crude glycerol-based polyol had reduced average cell size by more than 30% and slightly increased closed cell content, simultaneously reducing thermal conductivity coefficient of foam by 12% and inhibiting their thermal aging. Applied modifications showed also positive impact on the mechanical performance of rigid foams. Increase of crosslink density resulted in enhancement of compressive strength by more than 100%. Incorporation of prepared biopolyol resulted in enhancement of thermal stability and changes in degradation pathway. Up to 35 wt% share of crude glycerol-based polyol, foams showed similar flammability as reference sample, which can be considered very beneficial from the environmental point of view. 相似文献
11.
Aruna Palanisamy B. S. Rao Shaik Mehazabeen 《Journal of Polymers and the Environment》2011,19(3):698-705
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
12.
Subrata Mondal Paul Memmott Darren Martin 《Journal of Polymers and the Environment》2012,20(2):326-334
In this paper we explore the preparation of polyurethanes from spinifex resin biopolymer. Polyurethanes were prepared by both one-shot and pre-polymer (two step) processes. Attenuated total reflection??Fourier transform infrared analysis revealed urethane bond formation in both processes, and the peak intensity for N?CH stretching was more sharp when the network was prepared by the pre-polymer method. Gel permeation chromatography revealed that the molecular weight of synthesized polyurethane increased with respect to the resin starting material, and the molecular weight was further increased when polyurethane was synthesized by the pre-polymer method. The glass transition temperature was also increased for the polyurethanes as compared with the starting resin. Thermo-gravimetric analysis revealed that the thermal stability of the PU-spinifex resin was reduced at intermediate temperatures due to the urethane bond formation. However, thermal degradation properties were superior at higher temperatures due to the cyclization degradation reaction of spinifex-polyurethane. 相似文献
13.
S. Biswal J. R. Satapathy P. G. R. Achary N. C. Pal 《Journal of Polymers and the Environment》2012,20(3):788-793
Interpenetrating polymer networks from agricultural products such as glycerol modified castor oil polyurethanes and cardanol based dyes have not been extensively studied so far. Such polymers were synthesized using benzoyl peroxide as initiator and ethylene glycol dimethacrylate as cross-linker. Characterizations of these polymers were performed by Fourier Transform infra red spectra and thermal analysis techniques such as thermogravimetric analysis, derivative thermogravimetry and differential thermal analysis. The kinetic parameters such as activation energies and orders of reaction were estimated by using Freeman?CAnderson??s method. The effects of changes in polyurethane to dye monomer weight ratio and NCO/OH molar ratio of polyurethanes on the properties of such polymers were studied. 相似文献
14.
采用含有二乙二醇(DEG)和乙醇胺(ETA)的双组分解交联剂降解废旧硬质聚氨酯泡沫塑料(PU硬泡),并利用降解得到的低聚物多元醇与木质素复合制备出性能增强的再生PU硬泡。通过对制备的再生PU硬泡的红外光谱、密度、吸水率、抗压强度、热稳定性、导热系数、热重曲线等进行分析测试,考察m(DEG)∶m(ETA)对再生PU硬泡性能的影响。实验结果表明:m(DEG)∶m(ETA)=1∶3时废旧PU硬泡的降解效果最好;木质素加入量为2.0%(w)时再生PU硬泡的密度低、抗压强度高、保温性能良好,达到国家标准《建筑绝热用硬质聚氨酯泡沫塑料》(GB/T 21558—2008)的品质要求。 相似文献
15.
Swarnalata Sahoo Hemjyoti Kalita Smita Mohanty Sanjay K. Nayak 《Journal of Polymers and the Environment》2018,26(4):1528-1539
The current study focuses on the development of a formulation of polyester polyurethane (PEPU) samples using castor oil (CO) modified polyester polyol and partially biobased aliphatic isocyanate. The CO modified polyester polyol was synthesized employing transesterification reaction between CO and diethylene glycol in the presence litharge (PbO) catalyst. Subsequently, the modification of CO was confirmed using proton nuclear magnetic resonance (1HNMR) spectra analysis. In the next stage, the biobased polyester polyurethane nanocomposites (PEPUNC) were prepared by incorporating 3 wt% OMMT nanoclay within PEPU through in situ polymerization technique. The produced PEPU was confirmed by Fourier transform infrared spectroscopy (FTIR) and 1HNMR spectra analysis. Further, the degradation properties of developed PEPU subjected to soil-burial, UV exposure and hydrolytic-salt water medium were noted by FTIR spectroscopy. Corresponding weight loss, mechanical measurements and morphological studies through scanning electron microscopy (SEM) analysis were studied. The results showed that the addition of OMMT nanoclay within the PEPU matrix produces significant improvement in the degradation rate which indicated the susceptibility of OMMT nanoclay to humidity upon exposure to soil burial. The produced microorganisms from the soil resulted in significant chemical and morphological changes in the entire structure of the PEPU. Additionally, the highest degradation and percentage of weight loss was observed under soil burial as compared to UV exposure and hydrolytic-salt water medium. 相似文献
16.
Synthesis of Segmented Polyurethane Based on Polymeric Soybean Oil Polyol and Poly (Ethylene Glycol)
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
17.
R. K. Gupta M. Ionescu D. Radojcic X. Wan Z. S. Petrovic 《Journal of Polymers and the Environment》2014,22(3):304-309
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
18.
Rui Galhano dos Santos Noemi F. Acero Sandro Matos Ricardo Carvalho Mário Vale Ana C. Marques João C. Bordado Maria M. Mateus 《Journal of Polymers and the Environment》2018,26(1):91-100
The use of petroleum-derived products should be avoided regarding the principles of green and sustainable chemistry. The work reported herein, is aimed at the liquefaction of pine shavings for the production of an environmentally-friendly polyol suitable to be used in the formulations of sprayable polyurethane foams. The biopolyols were obtained in high yield and were used to replace those derived from fossil sources, to produce more “greener” polyurethane foams and therefore, less dependent on petroleum sources, since the polyol component was substituted by products resulting from biomass liquefaction. The partial and fully exchange of the polyols was accomplished, and the results compared with a reference foam. The foams were afterward, chemical, physical, morphological, and mechanically characterized. The complete replacement of polyether polyol and polyol polyester has presented some similar characteristics as that used as a reference, validating that the path chosen for the development of more sustainable materials is on the right track for the contribution to a cleaner world. 相似文献
19.
Ring-opening polymerization of cyclic esters (-caprolactone, -valerolactone, and l-lactide) onto liquefied biomass (LB) was conducted to obtain the polyester-type polyol and to regulate the characteristics of LB. IR and 1H-NMR spectra of the obtained polyol showed that the polymerization was successfully conducted in the presence of acid catalyst, which is used in liquefaction. The molecular weight (Mw), hydroxyl value, and viscosity were controllable by changing the reaction conditions. Polyester-type polyurethane foams with a wide range of properties were prepared from the obtained polyol with the appropriate combinations of foaming agents. 相似文献
20.
Janusz Datta Kamila Błażek Marcin Włoch Radosław Bukowski 《Journal of Polymers and the Environment》2018,26(12):4415-4429
A new efficient method for the chemical decomposition of polyamide 6.6 by the glycolysis and amino-glycolysis processes was proposed. The glycolysis was conducted using the mass excess of ethylene glycol (EG) as a decomposing agent in the presence of a catalyst. Also, a mixture of EG and triethylenetetramine was used as another decomposing agent in the amino-glycolysis process. The described process of decomposition did not require the use of elevated pressure. The hydroxyl and amine numbers, rheology behavior and the presence of characteristic chemical groups in the obtained glycolysates and aminoglycolysates were determined in order to characterize the reaction products. The decomposition products were defined as non-Newtonian fluids that could be described by suitable mathematical models. The conducted studies showed that the properties of the obtained intermediates depend on the mass excess of the decomposing agent used. The resulting semi-products are suitable for reusing in the synthesis of polyurethanes, which has been confirmed by the exemplary synthesis. In the reaction, 10 and 15 wt% of commercial polyol were replaced with the recovered intermediates. 相似文献