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1.
A new monomer, 1,2,3‐tris(ethoxycarbonyl)‐2‐propyl acrylate (TPA), was synthesized by reaction of acryloyl chloride and triethyl citrate. The homopolymer of TPA and its copolymers with acrylic acid (AA), vinyl acetate (VAc) and maleic anhydride (MAH) were prepared by polymerization using lauroyl peroxide (LPO) at 70 °C for 24 h. The structures of TPA and its polymers were identified by FTIR, 1H NMR, 13C NMR spectroscopies, and elemental analysis. The number average molecular weights and polydispersity indices of the synthesized polymers determined by GPC were in the range 4200–23 000 g mol?1 and 1.1–2.1, respectively. The IC50 values of the synthesized samples against cancer cell lines were greater than those of 5‐fluorouracil (5‐FU). The percentage inhibition values of SV40 DNA replication were 82.2 for TPA, 34.3 for poly (TPA), 81.9 for poly(TPA‐co‐AA), 82.0 for poly(TPA‐co‐VAc), 35.6 for poly(TPA‐co‐MAH) and 12.7 for 5‐FU. The inhibitions of SV40 DNA replication and antiangiogenesis for the synthesized TPA and its polymers are much greater than those of the control. © 2001 Society of Chemical Industry  相似文献   

2.
烯丙氧基聚乙氧基醚阻垢剂的合成与性能   总被引:2,自引:0,他引:2  
杜琨  周钰明  王莹莹 《化工学报》2008,59(1):249-255
以烯丙氧基聚乙氧基硫酸铵(APES)、马来酸酐(MA)、马来酸酐-丙烯酸共聚物(MA-AA)为原料,水为溶剂,使APES和MA、APES和MA-AA在水溶液中同时进行自由基共聚和接枝共聚,合成了APES接枝MA-AA的APES-MA聚醚型无磷的共聚物阻垢剂,用红外光谱和核磁共振氢谱对共聚物结构进行了表征。探讨了单体配比、温度和用量、黏均分子量对共聚物阻垢性能的影响,结果表明该阻垢剂既具有优异的阻Ca3(PO4)2性能,又有良好的阻CaCO3特性。温度80℃时,阻垢剂用量5 mg·L-1,阻Ca3(PO4)2率为98.89%;温度50℃时,用量5 mg·L-1,阻Ca3(PO4)2率为100.0%,用量25 mg·L-1,阻CaCO3率为97.97%。且CaCO3形成易被清除的松垢,该阻垢剂适用于工业循环冷却水系统。  相似文献   

3.
A new monomer, methacryloyl‐2‐oxy‐1,2,3‐propane tricarboxylic acid (MTCA), was synthesized from citric acid and methacrylic anhydride. Poly(methacryloyl‐2‐oxy‐1,2,3‐propane tricarboxylic acid) and poly(methacryloyl‐2‐oxy‐1,2,3‐propane tricarboxylic acid)‐co‐(maleic anhydride) were prepared by radical polymerizations. Terpoly(methacryloyl‐2‐oxy‐1,2,3‐propane tricarboxylic acid–maleic anhydride–furan) was obtained by in situ terpolymerization of MTCA and exo‐3,6‐epoxy‐1,2,3,6‐tetrahydrophthalic anhydride. The synthesized samples were identified by FTIR, 1H NMR and 13C NMR spectroscopies. The number‐average molecular weights of the fractionated polymers determined by GPC were in the range 14 900–16 600 and polydispersity indices were less than 1.14. The in vitro IC50 values of the monomer and polymers against cancer and normal cell lines were much higher than those of 5‐fluorouracil (5‐FU). The in vivo antitumour activities of the synthesized samples at a dosage of 0.8 mg kg−1 against mice bearing the sarcoma 180 tumour cell line decreased in the order terpoly(MTCA‐MAH‐FUR) > poly(MTCA‐co‐MAH) > poly(MTCA) > MTCA > 5‐FU. The synthesized samples inhibited DNA replication and angiogenetic activity more than did 5‐FU. © 2001 Society of Chemical Industry  相似文献   

4.
The radical‐initiated terpolymerization of 3,4‐dihydro‐2H‐pyran (DHP), maleic anhydride (MA), and vinyl acetate (VA), which were used as a donor–acceptor–donor system, was carried out in methyl ethyl ketone in the presence of 2,2′‐azobisisobutyronitrile as an initiator at 65°C in a nitrogen atmosphere. The synthesis and characterization of binary and ternary copolymers, some kinetic parameters of terpolymerization, the terpolymer‐composition/thermal‐behavior relationship, and the antitumor activity of the synthesized polymers were examined. The polymerization of the DHP–MA–VA monomer system predominantly proceeded by the alternating terpolymerization mechanism. The in vitro cytotoxicities of poly(3,4‐dihydro‐2H‐pyran‐alt‐maleic anhydride) [poly(DHP‐alt‐MA)] and poly(3,4‐dihydro‐2H‐pyran‐co‐maleic anhydride‐co‐vinyl acetate) [poly(DHP‐co‐MA‐co‐VA)] were evaluated with Raji cells (human Burkitt lymphoma cell line). The antitumor activity of the prepared anion‐active poly(DHP‐alt‐MA) and poly(DHP‐co‐MA‐co‐VA) polymers were studied with methyl–thiazol–tetrazolium testing, and the 50% cytotoxic dose was calculated. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2352–2359, 2005  相似文献   

5.
The purpose of this research was to synthesize and characterize a novel class of four‐arm, star‐shape biodegradable polymers having double‐bond functionality as a precursor for free‐radical polymerization, with unsaturated monomers or macromers or photocrosslinking for network formation. The synthesis involved two basic steps. First, hydroxyl‐functionalized four‐arm poly(?‐caprolactone)s (PPCL‐OH) were synthesized by the ring‐opening polymerization of ?‐caprolactone in the presence of pentaerythritol and stannous octoate. Second, double‐bond–functionalized four‐arm poly(?‐caprolactone)s (PPCL‐Ma) were synthesized by reacting PPCL‐OH with maleic anhydride in the melt at 130°C. Quantitative conversion of hydroxyl functionality in PPCL‐OH to double‐bond functionality was achieved for low molecular weight PPCL‐OH. Both the PPCL‐OH and the PPCL‐Ma were characterized by FTIR, 1H‐NMR, 13C‐NMR, SEC, and DSC. The capability of the double‐bond–functionalized four‐arm poly(?‐caprolactone)s (PPCL‐Ma) to form network structures was preliminarily shown by photocrosslinking PPCL‐Ma. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2296–2306, 2002  相似文献   

6.
Poly(adipic anhydride) (PAA) was prepared by the ring‐opening polymerization of adipic anhydride (AA) initiated by potassium poly(ethylene glycol)ate. The effects of various factors, such as the amount of initiator, concentration of the monomer, reaction time and temperature, and polarity of the solvent on the polymerization were investigated. The crude polymerized product was a mixture of PAA homopolymer and poly(ethylene glycol)–poly(adipic anhydride) block copolymer, as confirmed by 1H‐NMR and gel permeation chromatography. Chain‐transfer reactions occurred intensively for the AA polymerization in both the nonpolar solvent toluene and the polar solvents CHCl3 and tetrahydrofuran, which predominantly determined the molecular weight and the monomer conversion for the polymerized product. The lower monomer conversion in toluene was ascribed to a lower livingness for the initiator in the nonpolar solvent when compared with other two, polar solvents. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2194–2201, 2003  相似文献   

7.
The scale inhibitor was prepared based on itaconic acid (IA), styrene p-sulfonic sodium (SSS), maleic anhydride (MA), and acrylamide (AM) as monomers, and ammonium persulfate as an initiator by the free-radical polymerization. The structure of the polymer was characterized by FT-IR and UV-Vis spectroscopy. Using the static experiment method, the scale inhibition efficiency to CaCO3, the effects of some factors (concentration of polymer, time, concentration of Ca2+, pH value, concentration of HCO3 ?, and temperature) were investigated. Using the malachite green photometric method, the scale inhibition efficiency to Ca3(PO4)2 and the effects of some factors (concentration of polymer, time, Ca2+, pH, temperature, and the concentration of PO4 3?) were also investigated. The experimental results showed that the polymer had an excellent efficiency of scale inhibition and a resistance rate of calcium carbonate scale up to 96.67%, a resistance rate of calcium phosphate scale up to 92.5%, and could be used in the system of high-temperature and high-hardness water. The polymer had good dispersing ability with respect to iron.  相似文献   

8.
新型无磷无氮阻垢剂的阻磷酸钙垢及分散Fe(Ⅲ)性能   总被引:3,自引:1,他引:2       下载免费PDF全文
以烯丙基聚乙二醇单醚、氯乙酸、氢氧化钠、马来酸酐等为原料制备了一种新型无磷无氮环保型阻垢剂马来酸酐/烯丙基聚乙二醇羧酸钠(MCn,n为聚乙二醇聚合度,n=5、9、13),用红外光谱(FT-IR)、核磁共振(1H-NMR)等对阻垢剂结构进行了表征,采取静态阻垢率和含Fe(Ⅲ)溶液透光率的方法考察了阻垢剂阻磷酸钙和分散Fe(Ⅲ)性能,用扫描电镜(SEM)观察了阻垢后形成的磷酸钙形貌。结果表明,随着MCn结构中聚乙二醇聚合度n从5增加到13,其阻磷酸钙垢性能和分散Fe(Ⅲ)效果也逐步提高,其中MC13在投加量为6 mg·L-1时阻磷酸钙垢率达99%,在投加量为8 mg·L-1时使含Fe(Ⅲ)溶液的透光率为22%。MCn的高效阻磷酸钙垢和分散Fe(Ⅲ)能力是源于其侧链上含有聚乙二醇单醚结构及存在大量的-COO-离子且易与循环水系统中存在的不同的无机金属离子发生作用。  相似文献   

9.
The ring‐opening polymerization of ε‐caprolactone initiated with a divalent samarium bis(phosphido) complex [Sm(PPh2)2] is reported. The polymerization proceeded under mild reaction conditions and resulted in polyesters with number‐average molecular weights of 8.2 × 103 to 12.5 × 103. The yield and molecular weight of poly(ε‐caprolactone)s were dependent on the experimental parameters, such as the monomer/initiator molar ratio, the monomer concentration, the reaction temperature, and the polymerization time. The obtained polymers were characterized with Fourier transform infrared, NMR, gel permeation chromatography, and differential scanning calorimetry. On the basis of an end‐group analysis of low‐molecular‐weight polymers by NMR spectroscopy, a coordination–insertion mechanism is proposed for the polymerization. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1558–1564, 2005  相似文献   

10.
High‐molecular‐weight polymers of ϵ‐caprolactone (CL) and maleic anhydride (MA) with anhydride group content of about 1% wt have been synthesized and studied. The polymerization reaction was carried out in bulk under nitrogen atmosphere. Stannous octoate (Sn(oct)2), and 2,2'‐azobisisobutyronitrile (AIBN) were used as a catalyst and an initiator, respectively. A two‐level design of experiments was used to study the effect of various conditions on the characteristics of the copolymer. Reaction time, temperature, and concentration ratio of various reactants (two monomers, monomer to catalyst, and monomer to initiator) were the independent variables used, and the dependent variables included the molecular weight and the anhydride content in the polymer. Nuclear magnetic resonance (NMR) studies indicate that the succinic anhydride units were incorporated individually either to the polymer chain end or backbone. Anhydride content in the polymer and gel permeation chromatograph (GPC) studies indicate that the maleic anhydride acts as the true initiating species rather than as a comonomer in the system. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 3189–3194, 2000  相似文献   

11.
Ultrasonically initiated emulsion polymerization of n‐butyl acrylate (BA) without added initiator has been studied. The experimental results show that high conversion of BA can be reached in a short time by employing an ultrasonic irradiation technique with a high purge rate of N2. The viscosity average molecular weight of poly(n‐butyl acrylate) (PBA) obtained reaches 5.24 × 106 g mol?1. The ultrasonically initiated emulsion polymerization is dynamic and complicated, with polymerization of monomer and degradation of polymer occurring simultaneously. An increase in ultrasound intensity leads to an increase in polymerization rate in the range of cavitation threshold and cavitation peak values. Lower monomer concentration favours enhancement of the polymerization rate. 1H NMR, 13C NMR and FTIR spectroscopies reveal that there are some branches and slight crosslinking, and also carboxyl groups in PBA. Ultrasonically initiated emulsion polymerization offers a new route for the preparation of nanosized latex particles; the particle size of PBA prepared is around 50–200 nm as measured by transmission electron microscopy. © 2001 Society of Chemical Industry  相似文献   

12.
A novel series of water‐soluble polyester surfactants were prepared by the polymerization of bis‐1,4‐(dicarboxymethoxy) benzene, maleic anhydride, and oxypropylated 1,4‐butane diol (IP1–IP5) or oxypropylated 1,6‐hexane diol (IIP1–IIP5). The unique structural features of these surfactants were confirmed by IR and 1H‐NMR spectra. These water‐soluble polyester surfactants exhibited excellent surface tension, interfacial tension, low foaming, good emulsifier capability, and good biodegradability in river water, solubilization, wetting, and dispersant properties for applied dyes. The antimicrobial and antifungal properties of the prepared polyester surfactants were measured and found to be highly active. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3413–3424, 2001  相似文献   

13.
In this study, we first synthesized transparent poly(methyl methacrylate–maleic anhydride) [P(MMA–MAH)] and poly(methyl methacrylate–maleic anhydride–N‐2‐methyl‐4‐nitrophenyl maleimide) [P(MMA–MAH–MI)] via free‐radical polymerization at different monomer ratios. The synthesized polymers were characterized by titration, viscometric, spectroscopy, and thermal analyses. Higher contents of maleic anhydride (MAH) resulted in increases in the viscosity, glass‐transition temperature (Tg), and transparency. The synthesized polymers were then blended with a commercial‐grade poly(methyl methacrylate) (PMMA) used in aviation in the presence of CHCl3. According to the free volume theory, the incorporation of 5 wt % P(MMA–MAH)s or P(MMA–MAH–MI)s into the commercial PMMA resulted in a plasticizing impact on this thermoplastic, which was confirmed by the decrease in the Tg values of the blends with almost the same transparency as the initial PMMA. In fact, the higher the content of MAH was, the lower the Tg of the blends was. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46603.  相似文献   

14.
Deviation from nonlinear first order polymerization kinetic models is usually observed for cases where steric effects are dominant. A kinetic model was developed for the homo‐oligomerization of bulky maleic anhydride units. Factors affecting the kinetics of homo‐oligomerization of maleic anhydride have also been studied using two different initiators, azoisobutyronitrile (AIBN) and benzoyl peroxide, at 10 mol % concentrations in two different solvents o‐xylene and toluene. Maleic anhydride polymers having a number average molecular weight by SEC, between 300 and 900, and a polydispersity of between 1.0 and 2.0 were observed, and data were justified by the model. The molecular weight of the polymers increased with the conversion, and steric effects dominated at higher molecular weight as observed from the decrease in magnitude in the corresponding termination rate constants. The model values of conversion were compared with experimental data and cross verification of the model was done using molecular weight calculations. The present model represents the data with an average error of less than 5% over the entire experimental range. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3404–3412, 2006  相似文献   

15.
A hydrophilic copolymer (MA-APEA) containing carboxylic acid group and ethylene oxide group is synthesized from maleic anhydride (MA) and allyloxy polyethoxy carboxylic acid (APEA) in free radical polymerization and its structure is characterized using FT-IR, 1H nuclear magnetic resonance spectrometer and gel permeation chromatographic techniques. Seven polymer solutions with different degrees of deprotonation are prepared by adding caustic solution to the polymer solution. Effects of the degree of deprotonation of the polymer on curbing calcium scale and the corrosion inhibition of low carbon steel are studied. Influences of the operating conditions on inhibition against CaCO3 scale by the polymer with different degrees of deprotonation are also investigated. Effects of the degree of deprotonation on CaCO3 deposits/precipitate are analyzed using scanning electronic microscope and X-ray diffraction. The results show that different degrees of deprotonation of the polymer have different influences on different calcium scale and corrosion inhibition of low carbon steel. The performance of the polymer to withstand high alkalinity and high hardness and high temperature decreases with increase in the degree of deprotonation. The change in the degree of deprotonation influences the conversion of aragonite and vaterite to calcite, and hardly impacts the crystal morphology of CaCO3 crystals. MA-APEA has proven to be an excellent calcium scale inhibitor.  相似文献   

16.
A novel series of water‐soluble polyethylene glycol–polydimethylsiloxane (PEG–Silicone) polyesters was prepared by reacting organopolysiloxane with hydroxyl‐terminated polyester. The polyesters are obtained by the polymerization of maleic anhydride (MA) and PEGs (number‐average molecular weights M n = 2000–10,000). FTIR, 1H‐NMR, and elemental analysis were employed to characterized the structures of these compounds. These compounds exhibit good surface activities such as surface tension and low foaming. The influence of the PEG–Silicone polyester surfactants introduced at various concentrations (0.1–2 wt %) was examined by the contact angle method. The measurements performed with various solid substrates indicated that, at comparable concentrations, the PEG–Silicone polyester surfactants were shown to be more efficient for wetting PET and glass. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1236–1241, 2003  相似文献   

17.
Encapsulated nanometer calcium carbonate (nano‐CaCO3) was prepared using styrene and maleic anhydride (MAH) copolymer in 2‐propanol or methanol–water mixture in the presence of different initiator systems. The particle morphology and physical properties of the encapsulated nano‐CaCO3 particles, such as the interaction between the encapsulating polymer and the nano‐CaCO3, and the thermal stability of encapsulated nano‐CaCO3 were studied by Fourier‐transform infrared spectroscopy (FTIR), Soxhlet extraction experiments, thermogravimetric analysis banded with FTIR (TGA‐FTIR) and transmission electron microscopy (TEM). The encapsulating ratio and the stable encapsulating ratio of encapsulated nano‐CaCO3 were characterized. The results showed that a strong interfacial interaction was obtained due to the formation of a chemical bond or ion‐dipole between the C?O group of MAH and Ca2+ ion of nano‐CaCO3. The encapsulating ratio and stable encapsulating ratio of nano‐CaCO3 initiated by AIBN was higher than that initiated by BPO. Addition of maleic anhydride increased the encapsulating ratio and the stable encapsulating ratio of encapsulated nano‐CaCO3. For the encapsulated nano‐CaCO3 prepared in methanol–water, the diameter of the encapsulated nano‐CaCO3 particle increased from 60–70 nm to about 100 nm and the morphology changed from a cube with a sharp edge to spherical with a rough surface. Copyright © 2006 Society of Chemical Industry  相似文献   

18.
A new class of photoresist matrix polymers based on vinyl ether–maleic anhydride (VEMA) alternating copolymers was developed for ArF single‐layer lithography. These polymers were synthesized by copolymerization of alkyl vinyl ether and maleic anhydride alternating copolymers with acrylate derivatives containing bulky alicyclic acid‐labile protecting groups. The resulting polymers showed good control of polymerization and high transmittance. Also, these resists exhibited good adhesion to the substrate, high dry‐etching resistance against CF4 mixture gas (1.02 times the etching rate of deep UV resist), and high selectivity to silicon oxide etching. Using an ArF excimer laser exposure system with 0.6 NA, 120‐nm L/S patterns were resolved under conventional illumination. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 165–170, 2004  相似文献   

19.
The corresponding N‐hydroximide and N‐methyl‐N‐hydroximide of poly[ethylene‐alt‐(maleic anhydride)] (weight average molecular weight (Mw) of 100–500 g mol?1) were prepared as a new oral drug delivery system. Syntheses of N‐hydroximide and N‐methylhydroxamic acid of poly[ethylene‐alt‐(maleic anhydride)] were carried out by chemical modification of polymer with hydroxylamine and N‐methylhydroxylamine, respectively, to give water‐soluble polymers. These activated polymers were immobilized with ketoprofen in the presence of dicyclohexylcarbodiimide to give the corresponding water‐insoluble ketoprofen conjugates. All products were characterized by elemental analysis as well as Fourier transform infrared and 1H NMR spectra. In vitro release of ketoprofen was studied by measuring UV absorption at λmax = 260 nm as a function of time. This study demonstrated the potential use of N‐hydroximide and N‐methyl‐N‐hydroxamic acid of poly[ethylene‐alt‐(maleic anhydride)] as a drug delivery system. Controlled release was studied at different pH values and at different temperatures. At physiological temperature, the amount of drug released increased with increasing pH. The copolymer‐drug adducts released the drug very slowly at the low pH found in the stomach thus protecting the drug from the action of high acid conditions and resident digestive enzymes. These N‐hydroxamic acid polymer‐drug conjugates were found to be potentially useful in the delivery of macromolecular drugs to targeted sites in the lower gastrointestinal tract and the colon area. Copyright © 2007 Society of Chemical Industry  相似文献   

20.
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   

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