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1.
Novel pressure sensitive adhesives (PSAs) were developed from renewable methyl oleate (MO) and fully evaluated for their peel strength, tack force and shear resistance. MO was epoxidized and selectively hydrolyzed on the ester group to form epoxidized oleic acid (EOA) that is a bifunctional monomer containing both a carboxylic acid group and an epoxy group. EOA was step‐growth polymerized to form a hydroxyl‐containing polyester, which was then cured in the presence of a small amount of a polyfunctional epoxide [epoxidized soybean oil or trimethylolpropane triglycidyl ether (TMPTGE)] to afford PSAs. The PSAs from the polyester cured with TMPTGE exhibited high peel strength (2.4 N/10 mm), high tack force (5.8 N), and sufficient shear resistance (9.0 min). The PSAs can be fully based on renewable natural materials, and their preparations are environmentally friendly. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41143.  相似文献   

2.
A low‐residual siloxane‐modified polyacrylate pressure‐sensitive adhesive (PSA) with a high peeling strength was prepared by seeded semicontinuous emulsion polymerization. 3‐Glycidyloxypropyltrimethoxysilane was introduced into the acrylic (AC) PSA through a thermal posttreatment method to crosslink with AC. To improve the adhesion properties, a polymeric emulsifier, 2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid, was introduced into the system with the conventional emulsifier. Several key polymerization conditions, such as the initiator concentration, mass ratio of soft monomer to hard monomer, the content of polymeric emulsifier, and siloxane dosages were examined in detail. Then, the optimal conditions and a proper preparation process were established. The results show that we achieved not only a low repeeling residue with high tack and peeling strength but also excellent properties of high‐temperature aging resistance and water resistance. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42975.  相似文献   

3.
Thermotropic liquid‐crystalline polymers (TLCPs) have aroused considerable interest due to their attractive properties as high‐performance materials. Significant research attention has been devoted to investigating the relationship among monomer structures, syntheses and end‐use properties of TLCPs. The study reported here concerns the preparation, characterization and melt spinning of novel copolyesters containing two different flexible units together with two different aromatic units in the polymer chains. A range of copolyesters based on p‐hydroxybenzoic acid (p‐HBA), m‐hydroxybenzoic acid, p‐hydroxyphenylacetic acid and poly(ethylene terephthalate) were synthesized. The liquid crystallinity, thermal properties and degrees of crystallinity of these copolyesters were investigated using hot‐stage polarized light microscopy, differential scanning calorimetry, thermogravimetry and wide‐angle X‐ray diffraction. Copolyester fibres were characterized using scanning electron microscopy. The copolyesters were melt‐processable, thermally stable and could be processed above their melting temperatures without degradation. The degree of crystal structure was found to depend upon the content of p‐HBA. The fibres prepared showed that polymer chains had a well‐developed fibrillar structure. Novel TLCPs containing flexible units in the main chain were synthesized and characterized. Copolyesters containing p‐HBA units ranging from 55 to 70 mol% exhibited phase‐separated liquid‐crystalline morphology, appropriate melting temperatures and high thermal stability for melt processing. Copyright © 2010 Society of Chemical Industry  相似文献   

4.
A series of partial ladder copolymers were synthesized by chemically oxidative polymerization of m-phenylenediamine (MPD) and o-ethoxyaniline (EOA) using inorganic oxidants in inorganic acidic aqueous media. The polymerization yield, intrinsic viscosity, solubility, and thermal property of the copolymers were systematically studied by changing the comonomer ratio, initial polymerization temperature, polymerization time, oxidant, monomer/oxidant ratio, and acidic medium. As-prepared fine powder of the MPD/EOA copolymers was characterized by IR, UV-vis, and high-resolution 1H NMR spectroscopies and DSC. Circular dichroism technique was firstly used to characterize chain structure of the copolymers. The results showed that the oxidative polymerization from MPD and EOA is exothermic and the resulting copolymers exhibit a remarkably enhanced solubility in all of the organic and inorganic solvents chosen as compared with totally insoluble MPD homopolymer. The polymers obtained by the oxidative polymerization are real copolymers containing MPD and EOA units but do not contain MPD and EOA homopolymers based on a careful solubility comparison. The actual MPD/EOA molar ratio calculated based on 1H NMR spectra of the polymers is different from element analysis results. Element analysis indicated that denitrogenation happens during the polymerization linkage among MPD units and the structure consisting of MPD units is different from that reported. The ladder degree of the copolymers might be monitored by controlling MPD/EOA ratio. The DSC measurement indicates that the copolymers do not exhibit melt transition.  相似文献   

5.
Great achievements have been made in the research of biobased thermoplastic polymers, but the progress concerning thermosetting resins has been minor. In particular, research on high‐performance thermosetting polymers from renewable feedstock has not been reported elsewhere. A novel biobased epoxy was synthesized from a rosin acid. Its chemical structure was confirmed using 1H NMR, 13C NMR and Fourier transform infrared spectroscopy. The results indicated that the rosin‐based epoxy possessed high glass transition temperature (Tg = 153.8 °C), high storage modulus at room temperature (G′ = 2.4 GPa) and good thermal stability. A rosin‐based epoxy with excellent properties was achieved. The results suggest it is possible to develop high‐performance thermosetting resins from renewable resources. Copyright © 2010 Society of Chemical Industry  相似文献   

6.
A kind of novel poly(phenylene sulfide)s (PPSs) containing a chromophore group were synthesized by the reaction of dihalogenated monomer and sodium sulfide (Na2S.xH2O) via nucleophilic substitution polymerization under high pressure. The polymers were characterized by Fourier transform infrared spectroscopy, ultraviolet spectroscopy, fluorescence spectroscopy, XRD, DSC, TGA, mechanical testing and dissolvability experiments. The intrinsic viscosity of the polymers obtained with optimum synthesis conditions was 0.22 ? 0.38 dl g?1 (measured in 1‐chloronaphthalene at 208 °C). These polymers were found to have good thermal performance with a glass transition temperature (Tg) of 90.5 ? 94.6 °C and initial degradation temperature (Td) of 475–489 °C, showing improved thermal properties compared with homo‐PPS. At the same time the resultant resins had a high tensile strength of 67.5 ? 74.1 MPa and compressive strength of 70.7 ? 85.4 MPa. Additionally, these polymers exhibited a weak UV ? visible reflectivity minimum at 450–570 nm, and the fluorescence spectra of the polymers showed maximum emission around nearly 370 nm. Also they showed excellent chemical resistance and another special property ? bright shiny colors changed into different colors in acid solution. © 2014 Society of Chemical Industry  相似文献   

7.
A novel dinaphthodioxocin‐containing diol monomer, 8,16‐methano‐16H‐dinaphtho[2,1‐d:1′,2′‐g][1,3] dioxocin‐2,14‐diol (MDDD) was synthesized in high yield and purity through the condensation of 2,7‐dihydroxynaphthalene with malonaldehydetetramethyl acetal at room temperature. It is used as a new monomer for the synthesis of a series of novel dinaphthodioxocin‐containing aliphatic polyesters by interfacial polycondensation method. The new diol monomer was fully characterized by IR, NMR, mass spectroscopies, and elemental analysis. Optimal conditions for polyesterification were obtained via study of the model compounds. Polyesters derived from MDDD and four aliphatic diacid chlorides had inherent viscosities ranging from 0.26 to 0.38 dL/g. The chemical structure of the polymers was fully characterized by IR, NMR spectroscopies, and elemental analysis. The physical properties of the polymers were studied. All the new polymers show good thermal stability and very good solubility in most organic solvents. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

8.
A new polymerizable monomer, [4‐(9‐ethyl)carbazolyl]methyl methacrylate ( 2 ), was synthesized by reacting of methacrylic acid and 4‐hydroxymethyl‐9‐ethyl carbazole ( 1 ) by esterification procedure in the presence of N,N′‐dicyclohexylcarbodiimide. The resulting monomer was then polymerized free‐radically to form the poly(methyl methacrylate) containing 4‐(9‐ethyl)carbazolyl pend ent groups. Also, copolymerization of monomer 2 with various acrylic monomers such as methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, and n‐butyl acrylate by azobisisobutyronitrile as a free radical polymerization initiator gave the related copolymers in high yields. The structure of all the resulted compounds was characterized and confirmed by FTIR and 1H NMR spectroscopic techniques. The average molecular weight of the obtained polymers was determined by gel permeation chromatography using tetrahydrofurane as the solvent. The thermal gravimetric analysis and differential scanning calorimeter instruments were used for studying of thermal properties of polymers. It was found that, with the incorporation of bulky 4‐(9‐ethyl)carbazolyl substitutes in side chains of methyl methacrylate polymers, thermal stability and glass transition temperature of polymers are increased. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4989–4995, 2006  相似文献   

9.
A new optically active diacid (DA) was prepared by nucleophilic substitution reaction of R‐(−)‐mandelic acid with terephthaloyl chloride in the presence of potassium hydroxide. This DA named terephthalic acid bis(carboxyphenylmethyl) ester was used as a monomer for the preparation of related optically active polyesters. Polycondensation of DA with different aromatic diols, including hydroquinone, 1,5‐dihydroxy naphthalene, 1,4‐dihydroxy anthraquinone, 1,8‐dihydroxy anthraquinone, 2,4‐dihydroxy benzophenone, and bisphenol A, in the presence of 4‐toluenesulfonyl chloride using high temperature solution method led to preparation of different polyesters. The prepared monomer and all the polymers were characterized by conventional methods. Thermal and physical properties of the polyesters, including thermal stability, thermal behavior, solution viscosity, and solubility behavior, in addition to optical activity were studied. The optically active polyesters showed high thermal stability, whereas the presence of bulky groups improved their solubility. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

10.
以含硅多芳炔化合物(PSA)与1,3,5-三叠氮甲基-2,4,6-三甲基苯(TAMTMB)为原料,通过1,3-偶极环加成反应制备了新型含硅聚三唑树脂Si-PTA3,考察了树脂的流变性能、固化行为、热性能及单体配比对其热性能的影响。采用模压法制备了单向T700碳纤维增强的Si-PTA3树脂复合材料T700/Si-PTA3,测定了其力学性能。结果表明,Si-PTA3树脂具有良好的加工性能,可在80℃下固化,耐热性较好;炔基与叠氮基摩尔比为1.1:1.0时树脂固化物的热性能最好,玻璃化转变温度达334℃,在氮气中热失重5%时的温度达351℃;复合材料T700/Si-PTA3常温下的弯曲强度高于1670 MPa,250℃时弯曲强度保留率超过67%。  相似文献   

11.
A novel bio‐based polyamide, poly(pentamethylene oxamide) (PA52), with high molecular weight has been prepared from dibutyl oxalate and renewable monomer of 1,5‐pentanediamine by a two‐step polymerization procedure. The chemical structures are analyzed by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy while the properties are evaluated by differential scanning calorimetry, thermogravimetric analysis, and water uptake measurements for the obtained PA52. The results reveal that PA52 possesses distinguished properties such as high temperature resistance, excellent crystallizability and low water absorption. POLYM. ENG. SCI., 2017. © 2017 Society of Plastics Engineers  相似文献   

12.
The photoresponsive polyhedral oligomeric silsesquioxanes (POSS) based fluorinated azobenzene‐containing polymers were prepared and characterized by NMR, FT‐IR, GPC, XRD, TG and UV–Vis spectra. The thermal property of the polymers was improved by the introduction of POSS cage. The transcis photoisomerization of the polymers in solution was similar to that of the fluorinated azobenzene monomer and in accordance with the first‐order reaction kinetics equation within the first 250 seconds UV irradiation. The cotton fabrics coated with the polymers showed excellent water repellency and possessed switchable wettability under UV irradiation. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43540.  相似文献   

13.
A water-reducible alkyd resin was synthesized using the renewable resource canola oil and then chemically modified with styrene and the novel monomer acrylamido tertiary butane sulfonic acid (ATBS). Infrared spectroscopy and nuclear magnetic resonance techniques were used for structural elucidation of newly synthesized resins. Analyses of their physico-chemical and thermal properties revealed that styrene and ATBS-grafted water-reducible polymers have better thermal, chemical and coating properties than canola oil alkyd resins.  相似文献   

14.
Fluorine-containing poly-styrene-acrylate (PSA) latex with core–shell structure was successfully synthesized by seeded semicontinuous emulsion polymerization using fluorine monomer Actyflon-G04 and reactive emulsifier DNS-86. The chemical composition, morphology of latex, and surface composition of the latex film were characterized by Fourier transform infrared spectra, transmission electron microscopy, and X-ray photoelectron spectroscopy, respectively. The stability properties of latex were tested by Ca2+, centrifugal and mechanical stability tests, and the latex film was studied by water contact angle, water absorption ratio, and thermo-gravimetric analysis. The results show that fluorine-containing PSA latex particles with crosslinked core and crosslinked shell structure have excellent stability properties, and the film of latex has excellent water repellency, thermal stability, and chemical resistance properties when the amount of fluorine monomer was only 8.0 wt%.  相似文献   

15.
A novel ester diamine, 9‐(3,5‐diaminobenzoyloxy) fluorene, as a new monomer for preparation of polyimides was synthesized via two successive reactions. In the first step, reaction of 3,5‐dinitrobenzoylchloride with 9‐hydroxy fluorene in the presence of sodium hydroxide led to preparation of 9‐(3,5‐dinitrobenzoyloxy) fluorene. Second reaction was reduction of the nitro groups by tin (II) chloride and fuming hydrochloric acid to produce 9‐(3,5‐diaminobenzoyloxy) fluorene. The new diamine containing bulky fluorene group was characterized and polycondensed with different dianhydrides via two methods to produce polyimides. The new five‐membered and six‐membered ring polyimides were characterized and their properties including solubility behavior, inherent viscosity, thermal behavior and stability, and crystallinity were studied. They exhibited favorable balance of physical and thermal properties and their solubility were improved without sacrificing their thermal stability. Six‐membered rings polyimides showed higher thermal stability and lower solubility in comparison to related five‐membered ring polyimides. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

16.
A new aromatic diamine monomer containing benzoxazole substituents was prepared by a multistep synthesis starting from 1,4‐dibromo‐2,5‐difluorobenzene. The diamine was polymerized with commercial aromatic dianhydride or dicarboxylic acid chloride monomers to provide several different poly(amic acid)s and polyamides with their inherent viscosities in the range of 0.24–0.46 dL/g. Thermal properties of these polymers including thermal imidization of poly(amic acid)s into polyimides were investigated by using FTIR, DSC, and TGA. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 178–185, 2004  相似文献   

17.
This publication shows how the kind of crosslinking agents and their contents influence important properties of acrylic based pressure‐sensitive adhesive (PSA) dispersions such as tack, adhesion and cohesion. Synthesized PSAs based on acrylic polymers, containing 2‐ethylhexyl acrylate, butyl acrylate, vinyl acetate, styrene and acrylic acid are used in the preparation of self‐adhesive dispersions used as coating of polyethylene foams and poly(vinyl chloride) and polyester foils. © 2003 Society of Chemical Industry  相似文献   

18.
Petroleum based epoxy resins exhibit various excellent properties such as adhesion, mechanical performance, electrical insulation and chemical resistance. There is wide concern towards depletion of non‐renewable resources, climate change and finding renewable alternatives for petroleum based materials to reduce the emission of greenhouse gases. This review mainly draws attention towards the utilization of renewable resource based epoxy resin derived from lignocellulosic biomass, furan, tannins, itaconic acid, rosin acid and bio‐oil etc. Without altering the mechanical and thermal properties much, epoxy resins derived from renewable materials have been widely investigated. The last two decades have witnessed an exponential growth in using bio‐derived products, which has been driven by the need to replace petroleum based materials, reduce fuel consumption and lower the overall environmental impact. © 2018 Society of Chemical Industry  相似文献   

19.
Polymer chains consisting of water‐soluble polyacrylamides and N‐isopropylacrylamide (NIPAM), hydrophobically modified with low amounts of N,N‐dialkylacrylamides (N,N‐dioctylacrylamide) have been prepared via free radical micellar polymerization, using a hydrophobic initiator derived from 4,4′‐azobis(4‐cyanopentanoic acid) containing a long linear chain of 16 (C16) carbon atoms. This procedure resulted in polyacrylamides containing hydrophobic groups along the chain as well as at the chain ends. These polymers are named “combined associative polymers” and include within their structure a water‐soluble monomer (acrylamide), a thermosensitive monomer (NIPAM) and a hydrophobic monomer. The polymers were characterized by different techniques, also studying the effect of adding a surfactant anion such as sodium dodecylsulfate. The viscoelastic properties as a function of temperature of these associative polymers were investigated using steady‐flow and oscillatory experiments considering the relaxation time (TR) and the plateau modulus (G0). The effect of concentration of acrylamide and NIPAM on the viscosity of the associative polymer solutions was investigated. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers  相似文献   

20.
A new type of styrene monomer, 1‐{4‐[(4‐vinylbenzyl)oxy]phenyl}ethanone (VBOPE), was synthesized. The oxime, phenylhydrazone, toluol‐4‐sulfonic acid hydrazone, and thiosemicarbazone (TSC) derivatives of VBOPE were prepared with hydroxylamine hydrochloride, phenylhydrazine, toluol‐4‐sulfonic acid hydrazine, and TSC hydrochloride, respectively. Radical homopolymerization of the monomers were prepared at 65°C in 1,4‐dioxane solution with benzoylperoxide as an initiator. The compounds was characterized with Fourier transform infrared and NMR techniques. The thermal properties of polymers were investigated with thermogravimetric analysis and differential scanning calorimetry. The activation energies of the thermal degradation of the polymers were calculated with the Ozawa and Kissinger method. The antibacterial and antifungal effects of the monomer and the polymer and its derivatives were also investigated on various bacteria and fungi. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers  相似文献   

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