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1.
Summary α-Amino, ω-carboxyl heterodifunctional poly(methyl methacrylate) was prepared by a living anionic polymerization of methyl methacrylate using N,N'-diphenylethylenediamine monolithium amide and succinic anhydride as an initiator and terminator, respectively. Its intramolecular cyclization was carried out to obtain a well-defined cyclic poly(methyl methacrylate). Received: 27 June 2001/Accepted: 16 July 2001  相似文献   

2.
The carboxyl group-containing acrylic resin for powder coatings can be obtained by succinic anhydride reacting with hydroxyl group-containing acrylic resin, which was prepared by radical copolymerization of methyl methacrylate (MMA), n-butyl methacrylate (BMA) and β-hydroxypropyl methacrylate (HPMA) using 2,2′-azobisisobutyronitrile (AIBN) as initiator in toluene solution. The influence of synthesis method, weight ratio of monomers, and the amount of succinic anhydride on carboxyl group-containing acrylic resin was investigated. The 1H NMR results reveal that carboxyl group was successfully attached to acrylic resins. The optimum monomer weight ratio is MMA:BMA:HPMA = 65:20:15. The acid value of resin increases with the increasing of the amount of succinic anhydride, while the Tg of resin decreases.  相似文献   

3.
Dehydration and splitting of hydrogenated castor oil produces a mixture of fatty acids containing about 80% of the iso-oleic acids having the double bond in 11 and 12 positions in approximately equal proportions (as demonstrated by periodate/permanganate scission) and largely in the trans configuration. This technical iso-oleic acid reacts as expected with maleic anhydride to produce a mixture of isomeric iso-oleyl succinic anhydrides. When the oleate is reacted as the methyl ester the crude product can be distilled to produce methyl iso-oleyl succinic anhydride (M. O. S. A.) free from polymeric material. The yields of product under different conditions of time, temperature and ratio of maleic anhydride to fatty esters have been studied.  相似文献   

4.
Fatty acid methyl esters from low‐erucic and low‐linolenic rapeseed oil were used to produce alkenyl succinic anhydrides. A second‐order Doehlert uniform network design was used to investigate the influence of the reaction temperature and the molar ratio between the maleic anhydride and the main unsaturated rapeseed oil methyl esters on the yield of alkenyl succinic anhydride from methyl oleate. Further subjects of investigation were the conversion of methyl oleate, the formation of side reaction products, the Gardner color of the product and its viscosity, and finally the content of maleic anhydride remaining in the medium after the reaction. Alkenyl succinic anhydride from methyl oleate was isolated by column chromatography and analyzed by IR, 1H‐ and 13C‐NMR and MS. The optimal reaction conditions for obtaining the maximum yield of alkenyl succinic anhydride from methyl oleate in the experimental domain (80%) were 210‐220 °C and a maleic anhydride/rapeseed oil methyl ester molar ratio of 1.5. However, the products synthesized in these conditions showed a high degree of viscosity (0.45 kg m?1 s?1), a very dark color (18 Gardner color) and a high content of undesirable side products (6%), which could hinder their industrial use. A molar ratio of less than 1.5 led to a clearer and less viscous product, although with a lower alkenyl succinic anhydride content.  相似文献   

5.
In this study, styrene‐maleic anhydride (SMA) copolymer was modified by monoesterification method with 9‐(hydroxymethyl)anthracene fluorophore to prepare a fluorescent anthracene labeled SMA (SMA‐An) material. The latter was then characterized by attenuated total reflection (ATR) and thermogravimetric analysis (TGA) techniques. In the second step of this work, SMA‐An was added to SMA/[Styrene‐Acrylonitrile Copolymer (SAN)] and SMA/[Poly(methyl methacrylate) (PMMA)] blends to investigate the miscibility of these blends at the molecular level. The miscibility of SMA/PMMA blends was characterized using fluorescence quenching of anthracene by the succinic anhydride and succinic acid functions on SMA macromolecule itself. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007  相似文献   

6.
Sunflower oil and oleic motif-enriched sunflower oil methyl esters were used to prepare alkenyl succinic anhydrides. A classic batch reactor was selected to carry out the synthesis. The range in which the temperature, reaction time, and molar ratio between the number of moles of maleic anhydride and the equivalent number of double bonds present in the unsaturated vegetable oil methyl esters (the most influential factors in the process) varied was determined in a preliminary study. A secondorder Doehlert uniform network design was used to investigate the influence of the temperature and molar ratio for all the methyl esters on the yield of alkenyl succinic anhydride from methyl oleate, the conversion of methyl oleate, the formation of side reaction products, the Gardner color of the product, and viscosity. The optimal reaction conditions for obtaining the maximal yield (around 95%) of alkenyl succinic anhydride from methyl oleate were 235°C, a molar ratio of 1.5, and a reaction lasting 8 h. However, the products synthesized under these conditions showed high viscosity (215 cP), a very dark color (18+ Gardner color), and a high content of undesirable side products (4%), which hindered their direct industrial use. The increase in the product viscosity was probably due to the formation of side reaction products. A molar ratio of less than 1.5 led to a less viscous product, although with a lower alkenyl succinic anhydride content.  相似文献   

7.
Morphological and thermal properties of immiscible and incompatible polymer blends of commercial polyamide-6 (PA-6) and poly(methyl methacrylate) (PMMA) synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization have been studied in the presence of a compatibilizer consisting of either a random copolymer of styrene-maleic anhydride (SMA) or a diblock copolymer poly(methyl methacrylate) and polystyrene (PMMA-PS) also synthesized via RAFT polymerization. Blends of PA-6/PMMA were obtained by extrusion mixing. During melt compounding in the extruder, the functional groups of the polymer components were reacted in the presence of a compatibilizer, which changed considerably the morphology of the blend. After compatibilization, particles of PMMA in the PA-6 were smaller and better dispersed. The morphology and thermal properties of the blends were characterized using scanning electron microscopy (SEM) and differential scanning calorimetry (DCS).  相似文献   

8.
We have developed a two-step technique for synthesizing dichlorosuccinyl peroxide at room temperature, starting from succinic anhydride. It reacts with silanated glass fabric or beads at room temperature. The macroinitiator thus formed can be used for the polymerization of methyl methacrylate, MMA. We show that the MMA is grafted to the surface of glass giving a chemically bonded ultrathin coating, as confirmed by the FTIR analysis and electron micrography.  相似文献   

9.
Positron annihilation lifetime spectroscopy (PAL) was applied to study the feldspar effect on the free volume properties of crosslinked polyester based on neopentyl glycol, succinic acid, phthalic anhydride, and maleic anhydride. The measurements have been carried on the polyester resin samples cured with three crosslinking agents namely styrene (SS) or styrene/methyl methacrylate (SM) or styrene/acrylonitrile (SA) comonomers mixtures in the ratios of 2 : 1 and loaded with different concentrations of feldspar in the range from 0 to 80 wt %. The free volume parameters (size and fractions of holes) depend on type of the crosslinking agent as well as the feldspar content added to the polyester. The results are supported by a significant variation in the nanoscale free volume hole size distributions. Moreover, the correlation between positron annihilation parameters and electrical parameters was discussed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

10.
Abstract

Polyester-type UV absorbers were created by reacting the epoxy-functionalized UV absorber 2-hydroxy-4(2,3-epoxypropoxy)-benzophenone (HEPBP) with maleic, phthalic, or succinic anhydride. The ability of the UV absorbers to photostabilize wood was then examined. Fourier transform infra-red (FTIR) spectroscopy confirmed that HEPBP reacted with phthalic anhydride to create a polyester that preserved the UV-absorbing benzophenone group. There was less evidence that the polyester was formed when HEPBP was reacted with maleic or succinic anhydride. HEPBP-phthalic anhydride was the most effective UV absorber at photostabilising wood. This UV absorber showed increased UV absorption around 270 nm, formed a leach-resistant film at wood surfaces and was able to restrict both weight and tensile strength losses of thin wood veneers during accelerated weathering, unlike chromium trioxide and a UV absorber-hindered amine light stabilizer. We conclude that polymeric polyester-type UV absorbers show promise as a way of photostabilizing wood and briefly discuss how more effective systems could be developed in future.  相似文献   

11.
Prepolyesters were obtained from castor oil and dibasic acids, viz oxalic, malonic, succinic, glutaric, adipic, suberic and sebacic acid. These prepolyesters (PPE) were subsequently interpenetrated with methyl methacrylate containing 1% ethylene glycol dimethacrylate as crosslinker by radical polymerization initiated with benzoyl peroxide. The novel PPE poly(methyl methacrylate) PPE/PMMA interpenetrating polymer networks (IPNs) were obtained as powder. They were characterized by solubility behaviour, IR spectral study and thermal behaviour.  相似文献   

12.
Summary A catalytic process for synthesis of new polyesters with methacrylate pendant groups is presented. Thus, zinc succinate catalyzed reaction of succinic anhydride with glycidyl methacrylate (GMA) in dimethoxyethane gives linear oligoesters with low molecular weights (1380-2400 Da). The polyester formation takes place via simultaneous ring opening of the cyclic anhydride and oxirane units. GMA component can be partially replaced with cyclohexeneoxide to obtain polyesters with methacrylate pendant groups in various percentages. Nearly colorless waxy polymers are obtained in excellent yields (69–97%) within 48–60 h. at 90 °C. In the study structure of the polymers have been elucidated by conventional spectroscopic techniques and photo-crosslinking of ability of their thin films have been tested by monitoring intensity of methacrylate double bonds, using IR-spectrometry methodology.  相似文献   

13.
In this study, the copolymers of methyl methacrylate-co-glycidyl methacrylate (MGD) with different epoxy contents and molecular weights, the styrene-co-glycidyl methacrylate (SGD) and methyl methacrylate-co-maleic anhydride (MAD) were synthesized. The synthesized copolymers, styrene-co-maleic anhydride (SMA) and styrene-acrylonitrile-co-glycidyl methacrylate (SAG) were used as compatibilizers to enhance the impact strength of the acrylonitrile butadiene styrene/poly(butylene terephthalate) (ABS/PBT). The effects of differences in the structure, reactive group type, and molecular weight of the compatibilizers on the mechanical properties, phase morphology, melt viscosity, thermal stability, and melting temperature of the blend were studied. The results showed that functionalized copolymers were successfully synthesized with high monomer conversions. Addition of the functionalized copolymers increased melt viscosity but did not considerably affect thermal stability, tensile strength, flexural strength and melting temperature of the ABS/PBT blends. The compatibilizers improved the dispersion of the PBT phase and prevented brittle fracture, thereby increasing the impact strength of the blend. Among the studied compositions, the ABS/PBT/MGD-5 blend exhibited the highest impact strength of 25.8 kJ/m2 and an appropriate melt flow index of 19.1 g/10 minutes. The compatibilizer should have an appropriate molecular weight to improve the interface bonding force. Regarding the melting viscosity, the reactive group content and compatibilizer dosage should be adjusted to ensure high impact strength.  相似文献   

14.
葛虹  许培援  傅鹏立  朱冬梅 《化学世界》2004,45(3):141-143,147
在环己烷溶剂存在下,十八胺与顺丁烯二酸酐胺化后经Na2SO3磺化生成新型表面活性剂琥珀酸单十八酰胺磺酸钠(SOAS),反应最佳条件为:十八胺与顺丁烯二酸酐投料摩尔比1∶1.15,酰化反应温度70℃,酰化反应时间30min,顺丁烯二酸酐与亚硫酸钠投料摩尔比1∶1.10,磺化反应温度70℃,磺化反应时间3h,目的产物收率≥90%,测定出的SOAS应用性能表明其具有较高的发泡性和较低的脱酯率。  相似文献   

15.
Two p-allyloxyphenyldisiloxane compounds, 1-(p-allyloxyphenyl)-1,1,3,3,3-pentamethyldisiloxane (mono-APDS) and 1,3-bis(p-allyloxyphenyl)-1,1,3,3-tetramethyldisiloxane (bis-APDS), were synthesized to study their radical copolymerizations with some vinyl monomers (styrene, methyl methacrylate, N-phenylmaleimide and maleic anhydride). The reactivities of allyl groups in mono-APDS and bis-APDS were found to be almost the same in styrene and methyl methacrylate copolymerization, as evidenced by their composition curves, and increase with the electron-accepting ability of comonomers. In the case of electron-poor monomers, such as N-phenylmaleimide and maleic anhydride, the second allyl group of bis-APDS readily took part in the crosslinking. Differential scanning calorimetry and thermogravimetry revealed that the increase of APDS contents in those copolymers led to lower glass transition temperature (Tg) and higher thermal degradation temperature.  相似文献   

16.
The interfacial bondings formed between succinic acid and myristic acid, as well as succinic anhydride molecules with a set of differently treated zinc substrates have been investigated using infrared reflection absorption spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The compounds were selected to model typically used carboxylic-based adhesives and coatings. Moreover, the adsorption kinetic has been evaluated by means of chronoamperometry (CA) and chronovoltammetry measurements. XPS results showed a relation between the amount of carboxylates formed by adsorption of succinic acid/myristic acid and the hydroxyl fraction presented on the surfaces as proved by a higher electron transfer in CA. On the other hand a set of oxidative/reductive interactions was detected during the adsorption of succinic anhydride, in turn proving a spontaneous ring opening and adsorption mechanism. A clear relationship between the amount of adsorbents and surface hydroxyls/carbonates was detected for the adsorption of succinic anhydride. The extent to which the formed carboxylates resisted negative potentials was also investigated by cyclic voltammetry (CV) in an aqueous solution. The coordinative bonding of a bifunctional carboxylic acid group to the oxide surface was found to be not stable in the presence of a negative potential, while a monofunctional carboxylic acid group could resist displacement by water for a prolonged period of time. On the other hand, a low double layer capacitance was obtained after the adsorption of succinic anhydride, which was related to a change in potential of zero charge (PZC) upon the adsorption.  相似文献   

17.
N-Cyclohexylmaleimide (CHMI) was synthesized in high yield by dehydration and ring closure of N-cyclohexylmaleamic acid (CHMA) in an organic nonpolar solvent that is immiscible with water in the presence of a catalyst consisting of a mixture of acid and its amine salt. The optimal molar ratio of the acid to the amine is in the range of 1/0.65–1/0.8. N-Cyclohexylaminosuccinic anhydride (CASA), which is a major by-product, was found to induce coloration of the methyl methacrylate/CHMI copolymer. The CASA content could be decreased by distillation under reduced pressure. CHMI contaminated with less than 0.9 wt % of CASA can be used for heat-resistant poly(methyl methacrylate) resin (MMA/CHMI copolymer) free from coloration, as well as for methyl methacrylate homopolymer. © 1997 John Wiley & Sons, Inc.  相似文献   

18.
A series of poly(ester-urethane acrylate)/methyl methacrylate (PEUMA) crosslinked copolymers were prepared using hydroxyl terminated aromatic polyesters (PEs) with varying chain lengths. Four kinds of PEs with terminal hydroxyl groups were synthesized by reacting phthalic anhydride (PA) with 1,2- propanediol (PDO), 1,4-butanediol (BDO), 1,6-hexanediol (HDO) and diethylene glycol (DEG) respectively. The resultant PEs were reacted with isophorone diisocyanate (IPDI) in the presence of dibutyltin dilaurate (DBTDL) catalyst and end capped with 2-hydroxyethyl methacrylate (HEMA) to obtain ester-urethane-acrylate (EUA) prepolymer. Thereafter, crosslinked PEUMA copolymer were synthesized by reacting the EUA prepolymer with 40% (w/w) methyl methacrylate (MMA) in the presence of 1% azobisisobutyronitrile (AIBN) chain initiator. The PEs and EUA prepolymer were characterized by Fourier transform infrared (FT-IR) spectroscopy, 1H NMR, and gel permeation chromatography (GPC) techniques. The average molecular weights (Mc) between two crosslinks of the samples were determined by using the Flory Rehner equation. The tensile modulus, flexural strength, thermal properties and transparency of PEUMA copolymers were also determined and correlated with the average molecular weight and crosslinked density. The transparency of PEUMAs was found to be above 90% and hence it is an excellent alternative to glass for optical applications.  相似文献   

19.
A series of ultraviolet (UV)-curable waterborne hyperbranched polyurethane dispersions (WHPUDs) have been successfully synthesized by modifying the hyperbranched polyester H10, which was prepared using pentaerythritol as a core molecule and dimethylolpropionic acid as monomers, with succinic anhydride, toluene diisocyanate (TDI), and hydroxypropyl acrylate (HPA). The H10 was characterized by 1H nuclear magnetic resonance spectroscopy and matrix-assisted laser desorption/ionization time of flight mass spectrometry. The properties of the WHPUDs with different content of succinic anhydride and TDI–HPA have been investigated by measuring the stability, the particle size, and the rheological behavior. The effects of the content of succinic anhydride and TDI–HPA were studied in terms of UV-curing rate, water resistance, and thermogravimetric behaviors of WHPUD coatings. The WHPUDs showed good appearance, particle size, viscosity, and storage stability. The WHPUD films showed superior photosensitivity and the percent conversion of C=C bonds reached about 80% when the radiation time was 50 s. Moreover, the UV-cured films had good water resistance and thermostability, which can benefit a waterborne polyurethane resin for waterborne coatings.  相似文献   

20.
Poly(methyl methacrylate), poly(methyl methacrylate-co-2-hydroxyethyl methacrylate), poly(methyl methacrylate-co-itaconic acid), poly(methyl methacrylate-co-maleic anhydride), poly(methacrylic acid-co-itaconic acid), poly(methacrylic acid-co-maleic anhydride), and poly(itaconic acid) were prepared by copolymerization of the appropriate amounts of the two monomers at 50°C for 24–40 h using benzoyl peroxide as initiator. Selected samples were γ-irradiated with a total dose ranging from 2 to 12 Mrad. The unexposed and degraded polymers were dissolved in tetrahydrofuran and their molecular weight distribution was determined by gel permeation chromatography. It was found that M?n decreased drastically with increasing irradiation dose. The presence of various functional groups in both unexposed and irradiated samples was confirmed by infrared spectroscopy. The copolymer thermodynamic compatibility with various solvents was evaluated on the basis of their fractional solubility parameters. The Gs values of these copolymers were determined using the gel permeation chromatography data. It was established that, among those studied, poly(methyl methacrylate-co-maleic anhydride) is the best material for positive resist application based on a Gs value of 8 9 scissions per 100eV.  相似文献   

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