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1.
The syntheses of two linear unsaturated aromatic oligoesters, poly(hydroquinone fumarate‐co‐sebacate) (PHFS) and poly(resorcinol fumarate‐co‐sebacate) (PRFS), are described. PHFS, PRFS and poly(ethylene glycol) (PEG) are then used to prepare di‐ and tri‐block copolymers. Products thus obtained are investigated in terms of molecular weight, composition, structure and thermal properties by gel permeation chromatography (GPC), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and NMR and FTIR spectroscopies. A number of design parameters including the molecular weights of PHFS, PRFS and PEG and the ratios of PEG to PPFS or to PEFS are varied in order to assess their effects on product yields and properties. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2358–2363, 2003  相似文献   

2.
Polyacrylonitrile (PAN) and copolymer of acrylonitrile–vinyl acids prepared by solution polymerization technique have been characterized by Differential Scanning Calorimetry (DSC) (under dynamic as well as isothermal conditions), themograviemetric analysis (TGA), and on‐line DSC‐FTIR spectroscopy. The DSC of copolymers was carried out at 5°C/min in nitrogen and air. In nitrogen atmosphere the DSC exotherm show a very sharp peak, whereas, in air atmosphere DSC exotherm is broad, and starts at a much lower temperature compared to what is observed in nitrogen atmosphere. The initiation temperature of PAN homopolymer is higher than that for the copolymers. For instance, the initiation temperature of PAN in air is 244°C, whereas, the onset of exothermic reaction is in the range of 172 to 218°C for acrylonitrile–vinyl acid copolymers. As the vinyl acid content increases the ΔH value reduces. The ΔH value of PAN in air was 7025 J/g, whereas, for P(AN‐AA) with 5.51 mol % of acid it was 3798 J/g. As the content of acrylic acid comonomer is increased to 17.51 mol % the value of ΔH decreases further to 1636 J/g. The same trend was observed with MAA and IA as well. DSC‐FTIR studies depict various chemical changes taking place during heat treatment of these copolymers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 685–698, 2003  相似文献   

3.
o‐(2,2,3‐Tricyano‐3‐carbomethoxycyclopropyl)phenoxyethyl acrylate ( 5a ) and o‐(2,2,3‐tricyano‐3‐carbomethoxycyclopropyl)phenoxyethyl methacrylate ( 5b ) were prepared by reactions of bromomalononitrile with methyl o‐(2‐acryloyloxyethoxy)benzylidenecyanoacetate and methyl o‐(2‐methacryloyloxyethoxy)benzylidenecyanoacetate respectively. The dipole moments of 5a and 5b , calculated by atom superposition and electron delocalization molecular orbital method, were 2.75–3.47 D. Monomers 5a and 5b were polymerized with free‐radical initiators to obtain the polymers with tricyanocyclopropane ring as a piezoelectric chromophore in the pendant group. The resulting polymers 6a and 6b were soluble in common organic solvents such as acetone and DMF. Polymers 6a and b showed thermal stability up to 280 °C in TGA thermograms. Tg values obtained from DSC thermograms were in the range 125–140 °C. Piezoelectric coefficients (d31) of the poled films were 1.2–1.4 pC N?1. These polymers showed good temporal and long‐term thermal stabilities which are acceptable for piezoelectric device applications. Copyright © 2003 Society of Chemical Industry  相似文献   

4.
An experimental investigation on the kinetics of free-radical polymerization of behenyl (a mixture of 14.8% n-octadecyl, 15.1% n-docosyl) acrylate initiated with benzoyl peroxide was conducted at 70°C using a HAAKE rotational viscometer. Molecular weight measurements and differential scanning calorimetric studies of the samples are also described and the results are compared with those obtained by batch reactions conducted under a nitrogen atmosphere. A high monomer order of 1.61±0.11 and a low initiator order of 0.35±0.04 was obtained. The role played by the long methylene chain in behenyl acrylate is also discussed. © 1994 John Wiley & Sons, Inc.  相似文献   

5.
The polyacrylonitrile‐methyl acrylate (AN/MA mole ratio 100/0–70/30) copolymers and copolymers (AN/MA mole ratio 85/15) containing up to 40 wt % of microencapsulated n‐octadecane (MicroPCMs) are synthesized in water. The MicroPCMs were incorporated at the step of polymerization. The effect of the MA mole ratio and MicroPCMs content on structures and properties of the copolymers were studied by using Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H NMR), scanning electronic microscope (SEM), differential scanning calorimetry (DSC), thermogravimetry analysis (TG), gel permeation chromatography (GPC), and X‐ray diffraction (XRD). The feeding ratio agreed well with the composition of the AN/MA copolymers. The copolymers are synthesized in the presence of MicroPCMs. The melting point moves to lower temperature (206°C), while the decomposition temperature moves to higher temperature (309°C) with increasing of the MA mole ratio and microcapsules content. The number–average molecular weight of the copolymer is ~30,000. The crystallinity of the copolymer decreases with increasing of the MA mole ratio and microcapsules content. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2776–2781, 2007  相似文献   

6.
Multistage emulsion polymerization was used to prepare ultra‐high molecular weight foam regulator of low cost, with methyl methacrylate (MMA), butyl acrylate (BA), styrene (St) as main raw materials. Ubbelohde viscometer, dynamic light scattering, infrared and raman spectra, TEM, DSC, TGA, and GPC were all used to characterize constituent and structure, morphology, and molecular weight. As a result, when the ratio of soft monomer (BA) and hard monomer (St + MMA) is 1:3, MMA:St = 4:1, potassium persulfate (KPS): 0.15%, sodium hydrogen sulfite (SHS): 0.05%, azodiisobutyronitrile (AIBN): 0.15%, divinyl benzene (DVB): 0.3%, the final product terpolymer has obvious core‐shell structure and ultra‐high molecular weight (Mw = 1,400,000). This kind of foam regulator showed improvements in the melt strength, prevention of bubble coalescence and reduction on cost when compared with the traditional. Finally, the coefficients of poly (methyl methacrylate‐butyl acrylate‐styrene) terpolymer's Mark‐Houwink equation were calculated with tetrahydrofuran (THF) solvent at 25 °C. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44479.  相似文献   

7.
Free‐radical copolymerization of 4‐nitrophenyl acrylate (NPA) with n‐butyl methacrylate (BMA) was carried out using benzoyl peroxide as an initiator. Seven different mole ratios of NPA and BMA were chosen for this study. The copolymers were characterized by IR, 1H‐NMR, and 13C‐NMR spectral studies. The molecular weights of the copolymers were determined by gel permeation chromatography and the weight‐average (M w) and the number‐average (M n) molecular weights of these systems lie in the range of 4.3–5.3 × 104 and 2.6–3.0 × 104, respectively. The reactivity ratios of the monomers in the copolymer were evaluated by Fineman–Ross, Kelen–Tudos, and extended Kelen–Tudos methods. The product of r1, r2 lies in the range of 0.734–0.800, which suggests a random arrangement of monomers in the copolymer chain. Thermal decomposition of the polymers occurred in two stages in the temperature range of 165–505°C and the glass transition temperature (Tg) of one of the systems was 97.2°C. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1817–1824, 2003  相似文献   

8.
Poly(3‐hydroxy octanoate) (PHO), poly(3‐hydroxy butyrate‐co‐3‐hydroxyvalerate) (PHBV), and linoleic acid were grafted onto chitosan via condensation reactions between carboxylic acids and amine groups. Unreacted PHAs and linoleic acid were eliminated via chloroform extraction and for elimination of unreacted chitosan were used 2 wt % of HOAc solution. The pure chitosan graft copolymers were isolated and then characterized by FTIR, 13C‐NMR (in solid state), DSC, and TGA. Microbial polyester percentage grafted onto chitosan backbone was varying from 7 to 52 wt % as a function of molecular weight of PHAs, namely as a function of steric effect. Solubility tests were also performed. Graft copolymers were soluble, partially soluble or insoluble in 2 wt % of HOAc depending on the amount of free primary amine groups on chitosan backbone or degree of grafting percent. Thermal analysis of PHO‐g‐Chitosan graft copolymers indicated that the plastizer effect of PHO by means that they showed melting transitions Tms at 80, 100, and 113°C or a broad Tms between 60.5–124.5°C and 75–125°C while pure chitosan showed a sharp Tm at 123°C. In comparison of the solubility and thermal properties of graft copolymers, linoleic acid derivatives of chitosan were used. Thus, the grafting of poly(3‐hydroxyalkanoate) and linoleic acid onto chitosan decrease the thermal stability of chitosan backbone. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103:81–89, 2007  相似文献   

9.
Methyl methacrylate (MMA) has been copolymerized with n-butyl acrylate (n-BA), ethyl acrylate (EA), and 2-ethylhexyl acrylate (2-EHA) in solution at 70°C using benzoyl peroxide as free radical initiator. The copolymer composition was estimated by the 1H-NMR spectroscopic technique. The copolymers were further characterized by IR, XRD, TGA, DTA, DSC, GPC, and solubility. The adhesive characteristics of the copolymers to cellulosic substrate are also reported. © 1995 John Wiley & Sons, Inc.  相似文献   

10.
Poly(ethylene 2,5‐furandicarboxylate‐co‐ethylene succinate) (PEFS) copolymers of 2,5‐furandicarboxylic acid (FDCA) and succinic acid with 11.98–91.32 mol % FDCA composition were synthesized via melt polycondensation in the presence of ethylene glycol using tetrabutyl titanate as a catalyst. PEFSs' molecular weight, thermal properties, and molar composition were determined by Fourier transform infrared spectroscopy, gel permeation chromatography, intrinsic viscosity, 1H NMR, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and wide‐angle X‐ray diffraction (WAXD) measurements. From experimental conditions, we obtained random copolymers with number‐average molecular weights exceeding 25,600, determined by GPC and 1H NMR analyses. DSC analysis revealed that PEFS copolymers' melting temperatures differed depending on EF units' percentage. TGA studies confirmed that all PEFS copolymers' thermal stability exceeded 300°C. From WAXD analysis, it is observed that the PEFS copolymer crystal structure was similar to that of PES when EF unit was 11.98 mol % and to that of PEF when EF units were 74.35 and 91.32 mol %. These results benefit this novel biodegradable copolymer to be used as a potential biomaterial. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1415‐1420, 2013  相似文献   

11.
Homopolymers and copolymers were synthesized by polycondensation and copolycondensation, with varying feed ratios of bis(3‐hydroxypropyl terephthalate) (BHPT) and bis(4‐hydroxybutyl terephthalate) (BHBT) at 270°C. In addition, in the mol ratio of 1:1, copoly(trimethylene terephthalate/butylene terephthalate) [P(TT/BT)], with reaction times of 5, 10, 20, 30, and 60 min, was synthesized to identify the chain‐growth process of the copolymers. From differential scanning calorimetry (DSC) data, it was found that a random copolymer might be formed during copolycondensation. The molecular structure of copolymers, formed through the interchange reaction of BHPT and BHBT, was investigated using carbon nuclear magnetic resonance spectroscopy (13C‐NMR). We calculated the sequence‐length distributions of trimethylene and butylene sequences and randomness in the copolymers using 13C‐NMR data. From the values of the number‐average sequence length calculated, it was determined that a random copolymer was produced: This result coincides with previous DSC data. The lateral spacing of the unit cell of the copolymer increased slowly when the mol percent of one monomer was increased to that of the other monomer, indicating broadening of the unit cell by lateral distortion. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2200–2205, 2003  相似文献   

12.
2,5‐ Dichlorophenyl acrylate (DPA)‐co‐glycidyl methacrylate (GMA) polymers having five different compositions were synthesized in 1,4‐dioxane using benzoyl peroxide as a free‐radical initiator at 70 ± 0.5°C. Using 1H‐NMR spectroscopy, the composition of the two monomers in the copolymers was calculated by comparing the integral values of the aromatic and aliphatic proton peaks. The reactivity ratios were calculated by Fineman–Ross (r1 = 0.31 and r2 = 1.08), Kelen–Tudos (r1 = 0.40 and r2 = 1.15), and extended Kelen–Tudos (r1 = 0.39 and r2 = 1.16) methods. The nonlinear error‐in‐variables model was used to compare the reactivity ratios. The copolymers were characterized by 1H and proton decoupled 13C‐NMR spectroscopes. Gel permeation chromatography was performed for estimating the Mw and Mn and Mw/Mn of the poly(DPA) and copolymers (DPA‐co‐GMA: 09 : 91 and 50 : 50). Thermal stability of the homo‐ and copolymers was estimated using TGA [poly(DPA) > DPA‐co‐GMA (50 : 50) > DPA‐co‐GMA (09:91)], while DSC was utilized for determining the glass transition temperature. Tg increased with increased DPA content in the copolymer. The 50 : 50 mol % copolymer was chosen for curing with diethanolamine in chloroform. The cured resins were tested for the adhesive properties on leather at different temperatures (50, 90, 100, and 110°C). The resin cured at 50 °C exhibited a maximum peel strength of 1.6 N/mm, revealing a good adhesive behavior. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1167–1174, 2006  相似文献   

13.
The synthesis of triblock copolymer poly(octadecyl acrylate‐b‐styrene‐b‐octadecyl acrylate), using atom transfer radical polymerization (ATRP), is reported. The copolymers were prepared in two steps. First, polystyrene was synthesized by ATRP using α,α′‐dichloro‐p‐xylene/CuBr/bpy as the initiating system; Second, polystyrene was further used as macroinitiator for the ATRP of octadecyl acrylate to prepare ABA triblock copolymers in the presence of FeCl2·4H2O/PPh3 in toluene. Polymers with controlled molecular weight (Mn = 17,000–23,400) and low polydispersity index value (1.33–1.44) were obtained. The relationship between molecular weight versus conversion showed a straight line. The effect of reaction temperature on polymerization was also investigated, showing a faster polymerization rate under higher temperature. The copolymers were characterized by FTIR, 1H‐NMR, DSC, and GPC and the crystallization behavior of the copolymers was also studied. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1539–1545, 2004  相似文献   

14.
Amphiphilic copolymers of butyl acrylate (BA) and methyl methacrylate (MMA) with uniform polyoxyethylene (PEO) grafts were synthesized by the copolymerization of BA and MMA with a methacrylate‐terminated PEO macromer in benzene with azobisisobutyronitrile as an initiator. The effects of various copolymerization conditions on the grafting efficiency and molecular weight of the copolymers, as well as the effect of the copolymerization time on the conversions of the macromer and the monomers, were reported. The copolymers, with uniform PEO grafts, were purified by successive extractions with water and ether/acetone (3/7) to remove unreacted macromer and ungrafted copolymers of MMA and BA, respectively. The purified graft copolymers were characterized with IR, 1H‐NMR, membrane osmometry, gel permeation chromatography, and differential scanning calorimetry. The highest grafting efficiency was about 90%, and molecular weight of the copolymers varied around 105. The average grafting number of the copolymer was about 10. A study of the crystalline properties, emulsifying properties, phase‐transfer catalytic ability, and mechanical properties of the graft copolymers showed that the emulsifying volume decreased with the increasing molecular weight of the PEO grafts but increased with the PEO content. The conversion of potassium phenolate in the Williamson solid–liquid reaction obviously increased with an increasing PEO content of the graft copolymers. The crystallinity of the graft copolymers increased with the PEO content of the graft copolymers or the molecular weight of the macromer used. The copolymers, prepared under certain conditions, behaved as thermoplastic elastomers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2982–2988, 2003  相似文献   

15.
4-Chlorophenyl acrylate (CPA) was prepared by reacting 4-chlorophenol and acryloyl chloride in the presence of triethylamine in ethyl acetate solution. Poly(4-chlorophenyl acrylate) and copoly(4-chlorophenyl acrylate–methyl acrylate) were synthesized by the free radical polymerization in ethyl acetate at 70°C. All the polymers were characterized by infrared (IR) and nuclear magnetic resonance (NMR) spectroscopic techniques. The composition of the copolymers was determined by the 1H-NMR spectroscopic technique, that is, by integrating the aromatic peaks corresponding to the 4-chlorophenyl acrylate unit against the carbomethoxy group in the methyl acrylate unit. The reactivity ratios were calculated by Fineman–Ross, Kelen–Tudos (K–T), and the extended Kelen–Tudos methods. The values of r1 and r2 obtained by these methods were in close agreement with each other; that is, r1(CPA) = 0.64 and r2(MA) = 0.13 by the K–T method. The number-average molecular weight (M̄n = 1.55 × 103), the weight-average molecular weight (M̄w = 8.39 × 103), and the polydispersity index (M̄w/M̄n = 5.42) of poly(CPA) were determined by gel permeation chromatography (GPC). Thermal properties of the polymers were studied in a nitrogen atmosphere using thermogravimetric analysis (TGA). As the CPA increases in the copolymer, thermal stability of the copolymer increases (e.g., 90% weight loss occurs at 480°C for 20 mol % CPA, whereas the same weight loss occurs at 571°C for 80 mol % CPA). Acrylic binders, based on the CPA–MA–BA terpolymer, of different glass transition temperatures were prepared for applications in leather industry as top coat and base coat materials. These acrylic emulsions were cast into thin films, and their characteristics were tested for physical properties. These acrylic emulsions were applied as a base coat on leather, and the compositions having Tg values of 1.08 and 9.25°C were found to have excellent properties as base coats for leather when compared with commercial samples. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 1153–1160, 1999  相似文献   

16.
A series of aqueous latexes with solid contents of 56%–59% were synthesized by binary emulsion copolymerization of vinylidene chloride (VDC) with an acrylate, namely methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA), hexyl acrylate (HA), or 2‐ethylhexyl acrylate (EHA). Differential scanning calorimetry (DSC) and Fourier‐transform infrared (FTIR) spectroscopy showed that the acrylate units with short ester side‐chains, such as MA and EA, made the copolymers hard and the crystallization tendency of their PVDC segments was reduced. Hydrophobic acrylates with relatively long ester groups, such as HA and EHA, gave flexible copolymers, and favored the crystallization of their PVDC segments. BA endowed the copolymers with medium flexibility and crystallization tendency. As coating materials, the copolymers bearing MA and EA adhered poorly to the tinplate before or after 100 hr of salt‐spray corrosion, whereas those bearing BA, HA, or EHA showed good adhesion to tinplate when they had little or no crystallinity. After 100 hr of salt‐spray corrosion, only BA–VDC80, containing 80% VDC, retained both excellent adhesion to metal and excellent barrier performance. Further study demonstrated that BA–VDC80 could protect tinplate from rusting for at least 250 hr under harsh salt‐spray corrosion. Scanning electron microscopy, FTIR‐attenuated total reflectance spectroscopy and DSC were used to evaluate the corroded BA–VDC80 film. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40192.  相似文献   

17.
The positional effect of sulfonate groups on poly(butylene succinate) (PBS) microstructure was investigated. In this regard, unsaturated poly(butylene fumarate) (PBF) and poly(butylene succinate‐ran‐fumarate) copolymers, synthesized via esterification/polycondensation reactions, were modified through post‐polymerization modification. The progress of the PBF sulfonation reaction was analyzed via 1H NMR, dynamic light scattering and field emission SEM. The microstructure and thermal behavior of the functional polyesters were studied through DSC, TGA, elemental analysis and 1H NMR. Based on the results, the sulfonation reaction of unsaturated polymer chains, which are not experiencing a phase separation, is instantaneous, but sulfonation of the chains that have formed colloidal particles is a time‐consuming process. Surprisingly, the outcomes of 1H NMR analysis revealed a kind of heterogeneity along the fully sulfonated PBS backbone, similar to what is usually observed for copolymers. This is due to the ability of sulfonate groups to locate in different sites and create various block types. Due to the attraction between sulfonate groups, they tend to attach to the chain such that they provide the greatest number of second type blocks (containing two sulfonate groups). The randomness of sulfonated polymers after the sulfonation reaction was increased compared to that of the corresponding unsaturated copolymers. Increasing the content of sulfonate groups also led to a significant decrease in the thermal resistance (ca 120 °C) and crystallinity, along with a dramatic increase in ash content and Tg (up to 156 °C). © 2018 Society of Chemical Industry  相似文献   

18.
A series of triblock co‐polymers, consisting of a poly(ethylene glycol) (PEG) central block joined to two blocks of random p‐dioxanone‐co‐L ‐lactide copolymers were synthesized by ring‐opening polymerization of p‐dioxanone (PDO) and L ‐lactide (LLA) initiated by PEG in the presence of stannous 2‐ethylhexanoate catalyst. The resulting copolymers were characterized by various techniques including 1H and 13C NMR and FTIR spectroscopies, gel permeation chromatography, inherent viscosity, wide‐angle X‐ray diffractometry (WAXD) and differential scanning calorimetry (DSC). The conversion of PDO and L ‐lactide into the polymer was studied various mole ratios and at different polymerization temperature from 1H NMR spectra. Results of WAXD and DSC showed that the crystallinity of PEG macroinitiator was greatly influenced by the composition of PDO and L ‐lactide in the copolymer. The triblock copolymers with low molecular weight were soluble in water at below room temperature. © 2003 Society of Chemical Industry  相似文献   

19.
A novel perfluorinated acrylic monomer 3,5‐bis(perfluorobenzyloxy)benzyl acrylate (FM) with perfluorinated aromatic units was synthesized with 3,5‐bis(perfluorobenzyl)oxybenzyl alcohol, acryloyl chloride, and triethylamine. Copolymers of FM monomer with methyl methacrylate (MMA) were prepared via free‐radical polymerization at 80°C in toluene with 2,2′‐azobisisobutyronitrile as the initiator. The obtained copolymers were characterized by 1H‐NMR and gel permeation chromatography. The monomer reactivity ratios for the monomer pair were calculated with the extended Kelen–Tüdos method. The reactivity ratios were found to be r1 = 0.38 for FM, r2 = 1.11 for MMA, and r1r2 < 1 for the pair FM–MMA. This shows that the system proceeded as random copolymerization. The thermal behavior of the copolymers was investigated by thermogravimetric analysis and differential scanning calorimetry (DSC). The copolymers had only one glass‐transition temperature, which changed from 46 to 78°C depending on the copolymer composition. Melting endotherms were not observed in the DSC traces; this indicated that all of the copolymers were completely amorphous. Copolymer films were prepared by spin coating, and contact angle measurements of water and ethylene glycol on the films indicated a high degree of hydrophobicity. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

20.
The free‐radical copolymerization of 2‐metil‐1‐{[(1‐{4‐[(4‐nitrobenzil)oksi]fenil}etilidene)amino]oksi}prop‐2‐en‐1‐on (NBOEMA) with methyl methacrylate (MMA) was carried out in 1,4‐dioxane at 65 ± 1°C. The copolymers were analyzed by Fourier transform infrared spectroscopy, 1H‐NMR, 13C‐NMR, and gel permeation chromatography (GPC). Elemental analysis was used to determine the molar fractions of NBOEMA and MMA in the copolymers and for the characterization of the compounds. The monomer reactivity ratios were calculated according to the general copolymerization equation with the Kelen–Tudos and Fineman–Ross linearization methods. The polydispersity indices of the polymers, determined with GPC, suggested a strong tendency for chain termination by disproportionation. The thermal behaviors of the copolymers with various compositions were investigated by differential scanning calorimetry and thermogravimetric analysis. The glass‐transition temperature of the copolymers increased with increasing NBOEMA content in the copolymers. Also, the apparent thermal decomposition activation energies were calculated by the Ozawa method with a Shimadzu TGA 60H thermogravimetric analysis thermobalance. All of the products showed moderate activity against different strains of bacteria and fungi. The photochemical properties of the polymers were investigated by UV spectroscopy. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

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