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1.
Hyperbranched alkyd resins (HBRA) were synthesized by modification of hydroxylated hyperbranched polyester (HBP1‐4) with tall oil fatty acids (TOFA). The core is a hydroxylated hyperbranched polyester of fourth generation with OH groups in the periphery (18), which is endcapped with tall oil fatty acids. The occurrence of these reactions, HBP1‐4 and TOFA, was determined by making use of acid value, nuclear magnetic resonance, and hydroxyl values. The effects of TOFA and HBP1‐4 on properties of the HBRA resins were investigated by vapor pressure osmometry, differential scanning calorimetry, thermogravimetric analysis, friction resistance, and hardness. The resins with higher modification percentage (HBRA4) presented the best thermal and hydrolytic stability, but lower friction resistance and hardness. All HBRA resins presented amorphous characteristics, OH groups, and double bonds in the periphery. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

2.
Nowadays, so many studies are being carried out with the goal of obtaining environmentally friendly materials. In this study, styrene–hydroxyethyl acrylate copolymer (St‐co‐HEA) based alkyd resins with high solid contents and comb‐type structural morphologies were synthesized from St‐co‐HEA and macromonomers [MMs; dimethylol propionic acid modified with different proportions of tall oil fatty acids (TOFAs)]. The molar mass and gloss values of St‐co‐HEA were lower than those of the alkyd resins, but the thermal stability, viscosity, and glass‐transition temperature exhibited the opposite behavior. In all cases, the conversion percentage was higher than 80 %. The hydroxyl value and viscosity of the alkyd resins decreased with the TOFA content present in the MMrs, but the molar mass and the thermal stability increased. The rheological behavior of these resins was mainly pseudoplastic. Furthermore, the viscosity values were lower than 10 Pa s. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43996.  相似文献   

3.
Catalytic deoxygenation of tall oil fatty acids (TOFA) was demonstrated over palladium catalysts supported on mesoporous carbon at 300 °C using dodecane as a solvent. Maximally 95% selectivity to linear C17 hydrocarbons was achieved. The effects of reaction atmosphere and initial TOFA concentration were investigated.  相似文献   

4.
Banana fiber has been modified by treatments with sodium hydroxide, silanes, cyanoethylation, heat treatment, and latex treatment and the thermal degradation behavior of the fiber was analyzed by thermogravimetry and derivative thermogravimetry analysis. Both treated and untreated fibers showed two‐stage decomposition. All the treatments were found to increase the thermal stability of the fiber due to the physical and chemical changes induced by the treatments. The thermal degradation of treated and untreated banana fiber‐reinforced phenol formaldehyde composites has also been analyzed. It was found that the thermal stability of the composites was much higher than that of fibers but they are less stable compared to neat PF resin matrix. Composite samples were found to have four‐stage degradation. The NaOH treated fiber‐reinforced composites have very good fiber/matrix adhesion and hence improvement in thermal stability is observed. Though both silane treatments increased the thermal stability of the composite the vinyl silane is found to be more effective. Heat treatment improves the crystallinity of the fiber and decreases the moisture content, hence an improved thermal stability. The latex treatment and cyanoethylation make the fiber surface hydrophobic, here also the composite is thermally more stable than untreated one. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008  相似文献   

5.
About 1949, with the advent of effective fractional distillation, the tall oil industry came of age, and tall oil fatty acids (TOFA), generally any product containing 90% or more fatty acids and 10% or less of rosin, have grown in annual volume ever since, until they amount to 398.8 million pounds annual production in the U.S. in 1978. Crude tall oil is a byproduct of the Kraft process for producing wood pulp from pine wood. Crude tall oil is about 50% fatty acids and 40% rosin acids, the remainder unsaps and residues; actually, a national average recovery of about 1–2% of tall oil is obtained from wood. On a pulp basis, each ton of pulp affords 140–220 pounds black liquor soaps, which yields 70–110 pounds crude tall oil, yielding 30–50 pounds of TOFA. Separative and upgrading technology involves: (a) recovery of the tall oil; (b) acid refining; (c) fractionation of tall oil; and occasionally (d) conversion to derivatives. TOFA of good quality and color of Gardner 2 corresponds to above 97% fatty acids with the composition of 1.6% palmitic & stearic acid, 49.3% oleic acid, 45.1% linoleic acid, 1.1% miscellaneous acids, 1.2% rosin acids, and 1.7% unsaponifiables.  相似文献   

6.
The cellulose paper treated in proportional mixture systems showed higher liquid absorption compare to only EtOH and MeOH treatments. It was approximately 40–70% and 50–91% higher for EtOH-NaOH and MeOH-NaOH treated papers, respectively. All conditions apparently bring about an effect of decreased strength for papers. The lowest tensile strength of 13.0 N/mm was found with EtOH and NaOH treated samples after 5th repeating wetting-drying stage. But, some conditions gave approximately 21–59.5% higher stretch than untreated samples. The pore size distributions of papers were evaluated with Simons stain procedure and experimental results usually consisted with sorption data. The less intense CH2–CH2- vibrations (1450–1700 cm−1) and C-C and C-O-C peak areas in FTIR spectra indicates lowering H-bonds in solvent treated and dried paper network structure.  相似文献   

7.
The physical properties, thermal stability, and interaction with liquids of cellulosic fibers isolated from henequen fibers (Agave fourcroydes) by an alkaline digestion process were determined. Physical dimensions, apparent length, and diameter of henequen cellulosic fibers were determined by optical microscopy in a random sample of 125 fibers. Other properties such as crystallinity, specific gravity, and cellulose type were also determined. The sorption of several liquids in these cellulosic fibers was measured and correlated to the polar and hydrogen bonding components of the solubility parameters of the liquids. The results show that, in general, henequen cellulosic fibers have properties that are in close agreement with those found in other cellulosic materials from natural sources. © 1995 John Wiley & Sons, Inc.  相似文献   

8.
全色彩环保油墨   总被引:1,自引:0,他引:1  
张福凝 《山西化工》2006,26(2):58-61,72
通过分析油墨的基本组成可知:溶剂对环境的影响最大。与矿物油、植物油相比,源于木材加工业的松浆脂肪酸酯在油墨中作溶剂,其化学结构、黏度及挥发性能具有很多优点。而且,所制成的植物油型油墨在胶印性能、生物降解、气味、提高印刷效率方面效果极佳。目前,在环保要求与资源可再生性利用的压力下,植物油型油墨必将越来越受青睐。  相似文献   

9.
Tall oil is one of the side products from the kraft pulping process of lignocellulosic material. The most abundant acid found in this crude viscous material is abietic acid. Strangely, in the past, the utilization of tall oil has been limited to incineration for cogeneration of power. In this study, tall oil rosin acids (TORAs) were used in two different applications. First, it was used to enhance the hydrophobicity and thermal properties of hemp fibers. Second, TORAs were used to supplement epoxy for the production of a polymeric material. The reaction conditions from a model study were mimicked using a crude tall oil rosin acid mixture to enhance hemp fibers. Treated hemp fibers were characterized with increased surface hydrophobicity and improved thermal properties. Also, IR and X‐ray photoelectron spectroscopy confirmed successful chemical modification and grafting of carbon rich moieties onto the surface of the fibers, respectively. Furthermore, TORAs were used to supplement epoxy resin and produced plastics with comparable properties to pure epoxy based plastics. Specifically, 25% (w/w) replacement exhibited little difference in thermal stability and curing when compared to virgin epoxy plastics. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44327.  相似文献   

10.
Tall oil fatty acids (TOFA) were esterified with trimethylolpropane (TMP) without a catalyst at different molar ratios of TMP to TOFA. A molar ratio was defined, at which a polyol stable in long-term storage, with the maximum content of TMP monoesters, was synthesized. Fourier transform infrared spectroscopy and gas chromatography were used for the identification of the polyols’ chemical structure and composition. Based on the synthesized polyols, polyurethane coatings were prepared. The effect of the isocyanate index and concentration of traditional Sn-based and less toxic Bi-based catalysts on the gel time of the polyurethane composition, and the mechanical and thermal properties of the coatings was studied. It was found that the new coatings had high tensile strength and modulus of elasticity, comparable with the strength and modulus of the polyurethane based on diethanolamides of TOFA. The initial temperature of decomposition of these coatings was higher than that of the polyurethanes based on esters of TOFA and a number of uralkyds. The coatings based on TMP esters of TOFA were obtained without the use of solvents, and potentially, these esters can be used in spray-applied VOC-free polyurethane coatings’ formulation.  相似文献   

11.
Catalytic hydrogenation of linoleic acid and oleic acid to stearic acid over palladium on mesoporous carbon sibunit (Pd/sibunit) catalyst was studied in a continuous trickle-bed reactor with the weight hourly space velocity 5.4 h−1 at 120°C and 30 bar using tall oil fatty acid (TOFA) as reactor feed. Stearic acid preparation using TOFA as a raw material is of industrial importance. Pd/sibunit catalysts with spherical particle shape of the size 1.62 mm were synthesized with the palladium loadings 0.5, 1, and 2 wt %. The metal dispersion (%), metal particle size (nm), as well as metallic surface area (m2/g metal) of the three synthesized Pd/Sibunit samples were measured by CO chemisorption. The Pd/C catalysts were tested in linoleic acid hydrogenation, showing promising behavior in terms of activity, selectivity and stability to be used in fixed bed applications. The product stream from the fixed bed reactor was saved and analyzed by X-ray fluorescence (XRF) and direct current plasma (DCP) spectroscopy. The catalyst activity increased with the Pd loading. The lowest metal loading of 0.5 wt % gave the least prone to initial deactivation and thus the most stable catalyst. This catalyst can be recommended for farther pilot testing.  相似文献   

12.
Abstract

The present study concerns a practical approach to survey water sorption properties of ionic liquid ([EMIM]OAc) treated papers with and without chemical crosslinking. Ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate ([EMIM]OAc) can be used to transform sulfate pulp paper to regenerated cellulose film-like material. The fusion process increases both the dry and wet strength of the paper, improves oxygen and grease barrier properties, and increases paper transparency. The transformation is brought about by dissolution of the surfaces of the cellulosic fibers followed by precipitation and fusion of the fiber surfaces. Treatment conditions can be adjusted to produce partial dissolution of the fibers resulting in paper-like materials with improved wet-strength, or to achieve substantial or full dissolution resulting in transparent, regenerated cellulose film-like materials. From the industrial feasibility point of view, understanding the water sorption properties of IL-treated paper and the process parameters to control it are crucial. Results show that the treatment makes the paper more sensitive to both liquid water and water vapor, the magnitude depending on the degree of fiber dissolution and restraint of sheet shrinking during the treatment. Decreased water absorption and improved sheet dimensional stability were achieved by use of chemical crosslinking.  相似文献   

13.
The fabrication of high‐performance oil sorbents is of great significance for oil spill cleanup. The main objective of this study was to prepare open‐cell polypropylene/polyolefin elastomer (PP/POE) blend foams for fabrication of reusable sorbents for oil sorption. Open‐cell PP/POE blend foams were prepared via continuous‐extrusion foaming using supercritical carbon dioxide as the blowing agent. The interconnected open‐cell structure was characterized by scanning electron microscopy. The hydrophobicity and lipophilicity of PP/POE open‐cell foams were revealed by tests of contact‐angle measurement, water and cyclohexane sorption on the foam surface, CCl4 and cyclohexane sorption in water, and oil/water separation. Further, the sorption tests indicated that PP/POE blend foams showed larger oil‐uptake capacities than pure PP foams. In addition, cyclic compression tests showed that PP/POE open‐cell foams had excellent ductility and significantly improved recoverability compared to pure PP foams. In cyclic sorption–desorption tests, the sorption kinetics was studied in terms of capacity and saturation time, showing that PP/POE foams kept larger sorption capacities for 10 cycles, with larger sorption rates and good reusability. Based on the high open‐cell content, the good hydrophobic and oleophilic properties, the high oil‐sorption capacity, the improved recoverability, the large sorption rate, and the good reusability in cyclic oil‐sorption performance, the PP/POE open‐cell foams have shown promise as potential oil sorbents in applications for oil spill cleanup. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43812.  相似文献   

14.
Macromonomers (MMs) were obtained with different proportions of dimethylolpropionic acid (DMPA) and tall oil fatty acid (TOFA). The MMs were characterized by their acid value (AV), their hydroxyl value (OHV), IR spectroscopy, NMR, electrospray ionization–mass spectrometry, UV spectroscopy, rheological, differential scanning calorimetry, thermogravimetric analysis, gloss, flexibility, and adherence analyses. The presence of hydroxyl and ester groups and double bonds were confirmed by IR and NMR analyses. IR analysis showed that the intensity of the OH groups decreased with the addition of TOFA. In all cases, the AVs of the MMs were lower than those of DMPA and TOFA. By electrospray ionization–mass spectrometry, the formation of the DMPA homopolymers and structures with molecular weights higher than that of DMPA were observed. All of the MMs were amorphous. The viscosity of the MMs decreased with the addition of TOFA. The gloss values of the MMs at 85° were higher than 100, and the flexibility was good. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42029.  相似文献   

15.
Headspace gas chromatography-mass spectrometry (GC-MS) has been applied to the analysis of the temperature-dependent tall oil fatty acid (TOFA)/air partition coefficient (k 1) and the polydimethyl siloxane oil/air partition coefficient (k 2) of selected terpenes and low molecular weight solvents. As expected, both the TOFA and the silicone oil are effective trapping media for the nonpolar terpenes, but they are also efficient traps for acetone, methanol, n-propanol, and n-butanol. However, several species of low and moderate molecular weight (less than 150 amu) aldehydes, ketones, and organic acids that might adversely affect its trapping capacity were detected in the TOFA. This article will report the empirically gathered data and the subsequent calculation of the partition coefficients for the terpenes: α- and β-pinene, limonene, and α-terpineol and the solvents: acetone, methanol, n-propanol, and n-butanol between 50 and 130°C.  相似文献   

16.
Cellulose nanoparticles (CelNPs) prepared by an acid hydrolysis process were acetylated under ambient conditions to retain the nanosize and to obtain hydrophobic nanosized derivatives. Green nanocomposites of natural rubber (NR) with more than 50 phr of cellulosic fillers were successfully developed by a commercial dry mixing process. The incorporation of cellulose acetate nanofiller up to 40 phr led to an almost linear increase in both the tensile and elongation properties, which were higher than even those of a composite with the conventional filler carbon black (CB). This was further supported by the almost uniform single‐phase morphology of the nanobiocomposite revealed by scanning electron microscopy and the high thermal stability. The results indicate the high degree of compatibility between the hydrophobic nanosized filler and the NR matrix. Although a drop in the mechanical strength was observed above 50 phr, the cellulose derivatives were expected to prove to be promising substitutes for the hazardous filler CB even at higher loadings. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40632.  相似文献   

17.
This paper deals with the development of a cellulose acetate biopolymer. Plasticization of this biopolymer under varying processing conditions to make it a suitable matrix polymer for bio‐composite applications was studied. In particular, cellulose acetate was plasticized with varying concentrations of an eco‐friendly triethyl citrate (TEC) plasticizer, unlike a conventional, petroleum‐derived phthalate plasticizer. Three types of processing were used to fabricate plasticized cellulose acetate parts: compression molding, extrusion followed by compression molding, and extrusion followed by injection molding. The processing mode affected the physicomechanical and thermal properties of the cellulosic plastic. Compression molded samples exhibited the highest impact strength, tending towards the impact strength of a thermoplastic olefin (TPO), while samples that were extruded and then injection molded exhibited the highest tensile strength and modulus values. Increasing the plasticizer content in the cellulosic plastic formulation improved the impact strength and strain to failure while decreasing the tensile strength and modulus values. The coefficient of thermal expansion (CTE) of the cellulose acetate increased with increasing amounts of plasticizer. Plasticized cellulose acetate was found to be processable at 170–180°C, approximately 50°C below the melting point of neat cellulose acetate.  相似文献   

18.
19.
Regenerated cellulose biocomposite films from oil palm empty fruit bunch and microcrystalline cellulose were prepared using N,N-dimethylacetamide and lithium chloride. The effects of oil palm empty fruit bunch contents and butyl methacrylate on properties of regenerated cellulose biocomposite films were investigated. At 2?wt% of untreated oil palm empty fruit bunch content showed highest crystallinity index, tensile strength, modulus of elasticity, and thermal stability but lower elongation at break than other oil palm empty fruit bunch content. The treated regenerated cellulose biocomposite films with butyl methacrylate showed better tensile strength, modulus of elasticity, thermal stability, and crystallinity index while Fourier transform infrared spectroscopy study showed interaction between cellulose and butyl methacrylate.  相似文献   

20.
In this work, the citronella oil (CTO)‐loaded composite microcapsules with hydroxyapatite (HAp)/quaternary ammonium salt of chitosan (HACC)/sodium alginate (SA) shells are facilely and effectively fabricated by templating citronella oil‐in‐water Pickering emulsions, which are stabilized with HAp nanoparticles. The microcapsule composite shells are prepared by the electrostatic adsorption of HACC and SA, and then chelation interaction of alginate and Ca2+ ions released from HAp nanoparticles. Scanning electronic microscope observation shows that the microcapsules have a spherical shape. Thereafter, Fourier transform infrared spectroscopy and thermal gravimetric analysis results indicate that CTO is successfully loaded into the microcapsules, and the related CTO‐loaded microcapsules possess the thermal stability. Moreover, the in vitro release study of CTO shows that the microcapsules have sustained release activity, and the related CTO release profiles can be well described by Rigter–Peppas model. The antimicrobial assays of microcapsules display the antibacterial effect of CTO‐loaded microcapsules against Staphylococcus aureus and Escherichia coli. Overall, this study opens up new potentiality for unstable active ingredient as an environmental friendly and ingenious microencapsulation in food and agriculture applications. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46386.  相似文献   

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