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1.

New methacrylate monomers, 2‐{[(diphenylmethylene)amino]oxy}‐2‐oxoethyl methacrylate (DPOMA) and 2‐{[(1‐phenylethylidene)ami no]oxy}‐2‐oxoethyl methacrylate (MMOMA) were prepared by reaction of sodium methacrylate with diphenylmethanone O‐(2‐chloroacetyl) oxime and 1‐phenylethanone O‐(2‐chloroacetyl) oxime, respectively. They were obtained from a reaction of chloroacetyl chloride with benzophenone oxime or acetophenone oxime. The free‐radical‐initiated copolymerization of (DPOMA) and (MMOMA) with styrene (St) were carried out in 1,4‐dioxane solution at 65°C using 2,2‐azobisisobutyronitrile (AIBN) as an initiator with different monomer‐to‐monomer ratios in the feed. The monomers and copolymers were characterized by FTIR, 1H‐ and 13C‐NMR spectral studies. The copolymer compositions were evaluated by nitrogen content in polymers. The reactivity ratios of the monomers were determined by the application of Fineman–Ross and Kelen–Tüdös methods. The molecular weights (M¯w and M¯n) and polydispersity index of the polymers were determined by using gel permeation chromatography. Thermogravimetric analysis of the polymers reveals that the thermal stability of the copolymers increases with an increase in the mole fraction of St in the copolymers. The activation energies of the thermal degradation of the polymers were calculated with the MHRK method. Glass transition temperatures of the copolymers were found to decrease with an increase in the mole fraction of DPOMA or MMOMA in the copolymers. The antibacterial and antifungal effects of the monomers and polymers were also investigated on various bacteria and fungi. The photochemical properties of the polymers were investigated by UV and FTIR spectra.  相似文献   

2.
Abstract

Studies have been made on the characterizations and conductivities of poly(methyl vinyl ketone) (PMVK) and its copolymer with methyl methacrylate (poly(MVK-co-MMA)) after being reacted with phosphorus oxychloride (POCl3). The POCl3?treated polymers containing methyl vinyl ketone (MVK) were characterized by IR and UV spectroscopies to prove the structure of conjugated double bonds. The conductivities of all the MVK-containing polymers treated with POCl3 were very low, ca. 10?17 S/cm, in a vacuum regardless of the treatment time. The conductivities of the polymers when doped with iodine are in the range of the order of 10?4 to 10?6 S/cm. It was found that the conductivity of the POCl3?treated copolymer is slightly lower than that of PMVK.  相似文献   

3.
The radical homopolymerization of 5-nitrofurfuryl methacrylate (NFMA) and the copolymerization of NFMA with methyl methacrylate and various vinyl monomers, respectively, have been studied in dimethylformamide at 65°C. NFMA and poly(NFMA) have been characterized by 1H-NMR, IR, and UV spectroscopy. The influence of polymerization conditions on monomer conversion and on the molecular weight of the polymers obtained has been investigated. The thermal behavior of the polymers obtained has been studied by TGA and DSC analysis.  相似文献   

4.
Abstract

Phenacylmethacrylate (PAMA), a new monomer containing two carbonyl groups (C[dbnd]O), was obtained from phenacyl chloride and sodium methacrylate. The homopolymer of PAMA and its copolymer with styrene were prepared in dioxane by using benzoylperoxide (Bz2O2) as initiator. IR, 1H-NMR and 13C-NMR techniques were used to identify the structure of the monomer and polymers. The density of monomer, homopolymer and copolymer were found to be 1.13; 1.35 and 1.10 gr/ml respectively. Also, limit viscosity numbers, solubility parameters, glass transition and decomposition temperatures of polymers were determined.  相似文献   

5.
Copolymers of 4-cinnmoylphenyl methacrylate (CPMA) with glycidyl methacrylate were synthesized in methyl ethyl ketone solution using benzoyl peroxide as initiator at 70 ± 1°C. They were characterized by UV, IR, 1H-NMR, and 13C-NMR spectra. Their compositions were determined by 1H-NMR technique. The monomer reactivity ratios were determined by the Fineman-Ross and Kelen-Tüdös methods. The molecular weights ([Mbar]w and [Mbar]n) of the polymers were determined by GPC technique. Thermogravimetric analysis of the copolymers were carried out in air. The Tg of the polymers were determined by differential scanning calorimetry. The photocrosslinking properties of the homo and copolymers were also discussed.  相似文献   

6.

A new methacrylic monomer, 4‐nitro‐3‐methylphenyl methacrylate (NMPM) was prepared by reacting 4‐nitro‐3‐methyl phenol dissolved in methyl ethyl ketone (MEK) in the presence of triethylamine as a catalyst. Copolymerization of NMPM with methyl methacrylate (MMA) has been carried out in methyl ethyl ketone (MEK) by free radical solution polymerization at 70±1°C utilizing benzoyl peroxide (BPO) as initiator. Poly (NMPM‐co‐MMA) copolymers were characterized by FT‐IR, 1H‐NMR and 13C‐NMR spectroscopy. The molecular weights (Mw and Mn) and polydispersity indices (Mw/Mn) of the polymers were determined using a gel permeation chromatograph. The glass transition temperatures (Tg) of the copolymers were determined by a differential scanning calorimeter, showing that Tg increases with MMA content in the copolymer. Thermogravimetric analysis of the polymers, performed under nitrogen, shows that the stability of the copolymer increases with an increase in NMPM content. The solubility of the polymers was tested in various polar and non‐polar solvents. Copolymer compositions were determined by 1H‐NMR spectroscopy by comparing the integral peak heights of well separated aromatic and aliphatic proton peaks. The monomer reactivity ratios were determined by the Fineman‐Ross (r1 =7.090:r2=0.854), Kelen‐Tudos (r1=7.693: r2=0.852) and extended Kelen‐Tudos methods (r1=7.550: r2= 0.856).  相似文献   

7.
Abstract

Copolymers of 3-methoxy-4-acryloyloxybenzal phenylimine and methyl methacrylate with different feed ratios are synthesized in ethyl methyl ketone using benzoyl peroxide as a free radical initiator at 70 ± 1°CC. The polymers were characterized by IR and 1H-NMR spectroscopic techniques. Copolymer compositions were determined by lH-NMR analysis of the polymers. The monomer reactivity ratios were determined by the application of conventional linearization methods such as Fineman-Rose and Kelen-Tüdös. The molecular weights Mn and Mw of the polymers and the poly-dispersity index were determined by gel permeation chroma-tography. The intrinsic viscosities and the thermal properties of the homo-and copolymers are also discussed.  相似文献   

8.

Free‐radical homopolymerization and copolymerization of phenacyl methacrylate (PAMA) with methyl methacrylate (MMA) was done using 2,2′‐azobis(isobutyronitrile) (AIBN) as the initiator in 1,4‐dioxane at 60°C. 1H‐NMR and FT‐IR spectroscopy confirmed the existence of OCH2 and CH signals and unsaturated structure and CN stretch at the chain end of low molecular weight poly(phenacyl methacrylate)[poly(PAMA)], respectively. The six‐membered ring with both ester and ether at the end group was detected by 1H‐NMR. In the poly(PAMA), the end groups formed due to chain transfer reactions were found in large concentrations. The mechanism of the formation of end groups has been presented. The behavior of free radical polymerization of PAMA was compared with that of phenoxycarbonylmethyl methacrylate (PCMMA). The molecular weight distribution of the homo and copolymers was determined using gel permeation chromatography. Thermal properties of the polymers were determined using differential thermal analysis (DTA) and thermogravimetric analysis (TGA).  相似文献   

9.

Free‐radical homopolymerization and copolymerization of phenacyl methacrylate (PAMA) with methyl methacrylate (MMA) was done using 2,2′‐azobis(isobutyronitrile) (AIBN) as the initiator in 1,4‐dioxane at 60°C. 1H‐NMR and FT‐IR spectroscopy confirmed the existence of OCH2 and CH signals and unsaturated structure and CN stretch at the chain end of low molecular weight poly(phenacyl methacrylate) [poly(PAMA)], respectively. The six‐membered ring with both ester and ether at the end group was detected by 1H‐NMR. In the poly(PAMA), the end groups formed due to chain transfer reactions were found in large concentrations. The mechanism of the formation of end groups has been presented. The behavior of free radical polymerization of PAMA was compared with that of phenoxycarbonylmethyl methacrylate (PCMMA). The molecular weight distribution of the homo and copolymers was determined using gel permeation chromatography. Thermal properties of the polymers were determined using differential thermal analysis (DTA) and thermogravimetric analysis (TGA).  相似文献   

10.
用不同的方法合成了八种N-取代咔唑。测定了它们的红外光谱和核磁共振波谱。记录了各咔唑衍生物在CCl_4中不同光照时间的紫外-可见光谱。比较了各种咔唑衍生物单组份或与CCl_4组成的双组分体系对甲基丙烯酸甲酯光引发聚合活性。当N-烯丙基咔唑作为引发剂时,它参加了与甲基丙烯酸甲酯的共聚合反应。  相似文献   

11.
Acrylic anhydride (AAn) and methacrylic anhydride (MAAn) were polymerized with radical initiator in polar solvents at high temperatures. The polymers obtained were found to consist of five-and six-membered ring structures by comparing IR spectra of the polymers with those of model compounds, succinic anhydride, and glutaric anhydride. Hydrolysis and methylation of the polymers gave new polymers composed of head-to-head (HH) and head-to-tail (HT) methyl acrylate (MA) or methyl methacrylate (MMA) units. The content of HH unit of these HH/HT polymers was determined by 1H-NMR and 13C-NMR spectra. The softening, glass transition, and thermal degradation temperatures of the poly(MA) with HH and HT units were found to somewhat increase with increasing of the content of the HH units. On the other hand, the glass transition and thermal degradation temperatures of the poly(MMA) with HH and HT units increased similarly, but the softening temperature decreased as the content of the HH units increased.  相似文献   

12.
ABSTRACT

In this paper, the synthesis of a number of new methacrylate esters containing amide group are described. The monomers produced from the reaction of corresponding α-chloro-N-aryl or -N-alkyl acetamides with sodium methacrylate were polymerized with AIBN as initiator. The monomers and their polymers were characterized by IR, 1H- and 13C-NMR spectroscopy. The glass transition temperature and thermal decomposition temperature of the polymers were investigated by DSC-50 and TGA-50 thermobalance, respectively. The photocrosslinking properties of the polymers were also discussed.  相似文献   

13.
Reversible addition–fragmentation chain transfer (RAFT) mediated radical polymerizations of allyl methacrylate and undecenyl methacrylate, compounds containing two types of vinyl groups with different reactivities, were investigated to provide hyperbranched polymers. The RAFT agent benzyl dithiobenzoate was demonstrated to be an appropriate chain‐transfer agent to inhibit crosslinking and obtain polymers with moderate‐to‐high conversions. The polymerization of allyl methacrylate led to a polymer without branches but with five‐ or six‐membered rings. However, poly(undecenyl methacrylate) showed an indication of branching rather than intramolecular cycles. The hyperbranched structure of poly(undecenyl methacrylate) was confirmed by a combination of 1H, 13C, 1H–1H correlation spectroscopy, and distortionless enhancement by polarization transfer 135 NMR spectra. The branching topology of the polymers was controlled by the variation of the reaction temperature, chain‐transfer‐agent concentration, and monomer conversion. The significantly lower inherent viscosities of the resulting polymers, compared with those of linear analogues, demonstrated their compact structure. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 26–40, 2007  相似文献   

14.
Atactic cyclolinear organosilicon polymers carrying vinyl groups in RSiO1.5 or R2SiO moieties or concurrently in two moieties of the polymer unit have been synthesized by the heterofunctional polycondensation of 2,6-dihydroxymethyl(vinyl)cyclotetrasiloxanes with 2,6-dichloromethyl(vinyl)cyclotetrasiloxanes. The structure of the polymers has been studied by 1H and 29Si NMR spectroscopy, IR measurements, and elemental analysis. According to DSC, X-ray diffraction, and polarization optical microscopy, the polymers are amorphous in the range from ?100 to +200°C; the interlayer spacing and the type of packing remain unchanged with an increase in the content of vinyl substituents in the repeating units of cyclolinear polymethylvinylsiloxanes.  相似文献   

15.
The reaction of polyacrylonitrile with poly(vinyl alcohol) in dimethyl sulfoxide without any catalyst was studied, and it showed that the adjacent nitrile groups on polyacrylonitrile could be linked up to form conjugated carbon-nitrogen sequence by the presence of poly(vinyl alcohol). However, no such reaction occurred when poly(vinyl alcohol) was replaced by i-propanol or poly(vinyl alcohol) graft copolymers. The structure of the resulting polymers were proposed by means of IR, UV, 1H, and 13C-NMR spectroscopies. On the basis of the results, the effect of polymer feed and polymerization condition on this reaction were discussed. The compositions were determined by elemental analysis. The viscosity and thermal analysis of the products were also determined. At feed weight ratios of poly(vinyl alcohol) to polyacrylonitrile above one-half, gels were obtained.  相似文献   

16.
贾志峰  陈皞  颜德岳 《化学学报》2005,63(20):1861-1865
由甲基丙烯酸羟丙酯通过自缩合乙烯基氧阴离子聚合(self-condensing vinyl oxyanionic polymerization)制备了端羟基的超支化聚甲基丙烯酸酯. 以氢化钾(KH)和冠醚的复合物为引发剂时, 可以得到高分子量的聚合物. 用1H NMR和13C NMR谱图证实了聚合物的超支化结构. 由于在聚合过程中存在质子转移反应, 引发剂与单体的摩尔比会影响所得聚合物的结构. 超支化聚合物的玻璃化转变温度在58.1~81.4 ℃之间, 且随着引发剂与单体的比例的减小而降低. 当引发剂与单体等摩尔比时, 所得聚合物的支化度为0.49.  相似文献   

17.
A new monomer, 2,3,6,7,10,11‐hexa(methacrylate) triphenylene (HMTP), and its crystals have been successfully synthesized, and the solid‐state polymerization under UV irradiation has been investigated. The photo polymerization of HMTP in solid was confirmed by the reduction of vinyl bonds in the FT‐IR and UV spectra of PHMTP in comparison with the corresponding spectra of its precursor. Thus, IR spectroscope was used to follow the polymerization of HMTP crystals under UV irradiation, and kinetic studies show a first‐order reaction with rate constant of 6.12 × 10?3 min?1. This value is slightly larger than that measured by the weight method. The polarizing optical microscope and X‐ray diffraction were used to study the crystal structure difference between the polymers and its monomer. The results show that the polymers' crystals obtained from photo polymerization kept the monomer crystal lattice. Because of strong overlap between the π‐electron of the triphenylene, the monomer and polymer crystals showed different fluorescence properties. All these results proved that the photo polymerization of HMTP crystals is governed by the packing structure of monomer molecules; in other words, this reaction is just lattice controlled polymerization. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1526–1534, 2005  相似文献   

18.
Polymerization of acrolein(AL) in the presence of imidazole(Im) has been investigated in tetrahydrofuran or methanol below room temperature. The polymers obtained, white or pale yellow powders, were found to be composed of vinyl polymer with one Im group attached and having an aldehyde side chain, of which 70–80 mole % of the aldehyde revealed bridge structure. The number-average molecular weight (M n) of these polymers was determined to be in the range of 317 to 691. The rate of polmerization Rp was expressed by the equation, R + k[Im] [AL]2.

The addition of water or dimethyl sulfoxide accelerated the polymerization reaction, while the presence of benzaldehyde or N,N'-dimethylformamide decreased Rp. The structure of addition products in the initial polymerization step was confirmed by IR and NMR spectra, and the observations of polymerization system was carried out by UV and NMR spectra. The polymerization mechanisms were discussed on the basis of these results.  相似文献   

19.
Infrared spectroscopy has been used to monitor the polymerization of methyl methacrylate. Concentrations of methyl methacrylate in the reaction mixture were determined by use of three calibration methods. Classical quantitative analysis was used to measure the height of the stretching vibration bands of the vinyl group at 1639 cm–1. A calibration procedure using the considerably higher intensity of the C = O stretching vibration band of the carbonyl ester group at 1725 cm–1 seemed useful only for high concentrations of methyl methacrylate, i.e. at the beginning of reaction, because this band overlaps that of poly(methyl methacrylate). Use of second-derivative spectra and measuring their values at 1725 cm–1 enabled estimation of ten times lower concentrations of methyl methacrylate the calibration using the band from the vinyl group.  相似文献   

20.
The vinyl acetate centered triad fractions of some free radically prepared ethylene–vinyl acetate and styrene–vinyl acetate copolymers have been determined from the patterns of vinyl acetate methine carbon peaks in their 13C nuclear magnetic resonance (NMR) spectra. The positions and shapes of the carbonyl bands in the infrared (IR) absorption spectra of the copolymers recorded in chloroform are shown to depend on the compositions of the copolymers and on the proportions of the various vinyl acetate centered triads. Infrared absorption measurements may thus be used in part to characterize the monomer sequence distributions of these copolymers.  相似文献   

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