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Effect of Methyl Methacrylate– Acrylonitrile -Butadiene–Styrene (MABS) on the Mechanical and Thermal Properties of Poly (Methyl Methacrylate) (PMMA)-Fly Ash Cenospheres (FAC) Filled Composites 被引量:1
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作者 M. B. Kulkarni P. A. Mahanwar 《Journal of Minerals and Materials Characterization and Engineering》 2012年第4期365-383,共19页
With the advent of plastics and the wide range of fillers that are available have made modifications as precise as the tailored resins themselves. To modify the properties of polymer either by using fillers or by prep... With the advent of plastics and the wide range of fillers that are available have made modifications as precise as the tailored resins themselves. To modify the properties of polymer either by using fillers or by preparation of polymer blends gives rise to new materials with tailored properties. More complex, three-component systems, obtained by the addition of polymeric modifier to polymer filled composites may be of interest. Use of Fly ash cenospheres is very attractive because it is inexpensive and its use can reduce the environmental pollution to a significant extent. In the present study, Poly (Methyl Methacrylate) (PMMA)-Fly ash cenospheres composites were prepared using extrusion followed by Injection molding. The effect of matrix modification with Methyl methacrylate– acrylonitrile -butadiene–styrene (MABS) on the performance of PMMA- Fly ash cenospheres compositions was also, studied. It was found that with the addition of Fly ash cenospheres particulate as filler in PMMA showed marginal reduction in Tensile Strength, % Elongation and Impact strength and improvement in Flexural Strength, Heat Deflection Temperature and Vicat Softening Point. Compared with PMMA-cenospheres composites, the notched Impact Strength of the PMMA/MABS/cenospheres composites showed marginal enhancement in values at higher loading of cenospheres. The optimum performances in mechanical and thermal properties were obtained when the ratio of MABS to cenospheres was 1:2. 展开更多
关键词 poly (methyl methacrylate) (pmma) Fly ash cenospheres (FAC) methyl methacrylate ACRYLONITRILE -butadiene–styrene (MABS) Mechanical and Thermal Properties.
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Polybutylacrylate/poly(methyl methacrylate) Core-Shell Elastic Particles as Epoxy Resin Toughener: Part I Design and Preparation 被引量:6
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作者 JianliWANG MyonghoonLEE +2 位作者 XiaomeiYU JianbinJI KejianYAO 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第5期522-526,共5页
Polybutylacrylate (PBA)/poly(methyl methacrylate) (PMMA) core-shell elastic particles (CSEP), whose rubbery core diameter ranged from 0.08 μm to 1.38μm, were synthesized by using conventional emulsion polymerization... Polybutylacrylate (PBA)/poly(methyl methacrylate) (PMMA) core-shell elastic particles (CSEP), whose rubbery core diameter ranged from 0.08 μm to 1.38μm, were synthesized by using conventional emulsion polymerization, multi-step emulsion polymerization, and soapless polymerization. Allyl methacylate (ALMA) and ethylene glycol dimethacrylate (EGDMA) were selected as crosslinking reagents for core polymerization. Methacrylic acid (MAA) was used as functional co-monomer with methyl methacrylate as shell component. The content of vinyl groups in PBA rubbery core increased with the amount of crosslinking reagents. The core-shell ratio affected great on the morphology of the complex particles. Furthermore, the amounts of carboxyl on the surface of core-shell particles, copolymerized with acrylic acid, were determined by potentiometric titration. Results showed that methylacrylic acid was distributed mostly on the surface of particles. 展开更多
关键词 Core-shell polymers polybutylacrylate poly(methyl methacrylate) Epoxy resin
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AN ATOMIC FORCE MICROSCOPY STUDY ON THE AGGREGATION OF ISOTACTIC POLY(METHYL METHACRYLATE) 被引量:2
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作者 Jing Liu Ji-jun Wang +4 位作者 Ting Li Yong Zhou De-yan Shen Yun Huang Shou-ke Yan 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第2期207-215,共9页
Aggregation process of isotactic poly(methyl methacrylate) (i-PMMA) has been studied extensively for many years, and considerable progress has been made in both experimental and theoretical studies. They are, howe... Aggregation process of isotactic poly(methyl methacrylate) (i-PMMA) has been studied extensively for many years, and considerable progress has been made in both experimental and theoretical studies. They are, however, seldom sustained by real-space observations of the underlying morphology. In this paper, the aggregation process of i-PMMA in concentrated acetone solutions and the fractal structure of the resulting three-dimensional clusters were characterized on the basis of real-space AFM observations of their two-dimensional projection. It was found that spherical multiple-chain particles formed upon collapse and aggregation of the involving chains as a whole during quenching the solution to room temperature. By keeping the solution at room temperature, the initially formed particles stick together upon contact to form larger particles through reassembling very slowly. The succeeding collision of the enlarged spherical particles leads to the formation of small clusters. These newly formed small clusters grow when they meet with other clusters or single Brownian particles. This leads to the formation of large clusters with fractal dimension of 1.95 ± 0.05, which suggest a reaction-limited cluster aggregation of i-PMMA in a concentrated acetone solution. This is in accordance with the conclusion obtained by light scattering measurements. 展开更多
关键词 Isotactic polymethyl methacrylate) AGGREGATION Fractal dimension Atomic force microscopy.
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Synthesis of Comblike Poly(methyl methacrylate) by Atom Transfer Radical Polymerization with Poly(ethyl 2-bromoacrylate) as Macroinitiator 被引量:2
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作者 YanSHI ZhiFengFU +1 位作者 YuDongZHANG ShuKeJIAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第12期1289-1292,共4页
Comblike poly(methyl methacrylate) was synthesized by atom transfer radical polymerization of methyl methacrylate with poly(ethyl 2-bromoacrylate) as a macroinitiator, which was prepared by conventional free radical p... Comblike poly(methyl methacrylate) was synthesized by atom transfer radical polymerization of methyl methacrylate with poly(ethyl 2-bromoacrylate) as a macroinitiator, which was prepared by conventional free radical polymerization of ethyl 2-bromoacrylate. The obtained comblike polymers were characterized by GPC and 1H NMR. 展开更多
关键词 Comblike polymer atom transfer radical polymerization (ATRP) MACROINITIATOR poly(methyl methacrylate) ethyl 2-bromoacrylate.
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PREPARATION OF POLY(METHYL METHACRYLATE)/LAYERED DOUBLE HYDROXIDES NANOCOMPOSITES via in situ SOLUTION POLYMERIZATION 被引量:2
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作者 Ang-ran Wang Yong-zhong Bao Zhi-xue Weng Zhi-ming Huang 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第6期573-579,共7页
An exfoliated layered double hydroxides/poly(methyl methacrylate) (LDHs/PMMA) nanocomposite was prepared by in situ solution polymerization of methyl methacrylate (MMA) in the presence of 4-vinylbenzenesulfonate... An exfoliated layered double hydroxides/poly(methyl methacrylate) (LDHs/PMMA) nanocomposite was prepared by in situ solution polymerization of methyl methacrylate (MMA) in the presence of 4-vinylbenzenesulfonate intercalated LDHs(MgAl-VBS LDHs). MgAl-VBS LDHs was prepared by the ion exchange method, and the structure and composition of the MgAl-VBS LDHs were determined by X-ray diffraction (XRD), infrared spectroscopy and elemental analysis. XRD and transmission electron microscopy (TEM) were employed to examine the structure of LDHs/PMMA nanocomposite. It was indicated that the LDHs layers were well exfoliated and dispersed in the PMMA matrix. The grafting of PMMA onto LDHs was confirmed by the extraction result and the weight fraction of grafted PMMA increased as the weight fraction of LDHs in the nanocomposites increased. 展开更多
关键词 NANOCOMPOSITE polymethyl methacrylate) Layered double hydroxides.
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Effect of Low-Pressure Nitrogen DC Plasma Treatment on the Surface Properties of Biaxially Oriented Polypropylene, Poly (Methyl Methacrylate) and Polyvinyl Chloride Films 被引量:2
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作者 S. Hamideh MORTAZAVI Mahmood GHORANNEVISS +4 位作者 Soheil PILEHVAR Sina ESMAEILI Shamim ZARGHAM S. Ebrahim HASHEMI Hamzeh JODAT 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第4期362-367,共6页
In this study, commercial biaxially oriented polypropylene (BOPP), polyvinyl chlo- ride (PVC) and poly (methyl methacrylate) (PMMA) films were treated with nitrogen plasma over different exposure times in a Py... In this study, commercial biaxially oriented polypropylene (BOPP), polyvinyl chlo- ride (PVC) and poly (methyl methacrylate) (PMMA) films were treated with nitrogen plasma over different exposure times in a Pyrex tube surrounded by a DC variable magnetic field. The chemi- cal changes that appeared on the surface of the samples were investigated using Fourier transform infrared (FT4R) spectroscopy and attenuated total reflectance Fourier transform infrared (ATR- FTIR) spectroscopy after treatment for 2 min, 4 min and 6 rain in a nitrogen plasma chamber. Effects of the plasma treatment on the surface topographies and contact angles of the untreated and plasma treated films were also analyzed by atomic force microscopy (AFM) and a contact angle measuring system. The results show that the plasma treated films become more hydrophilic with an enhanced wettability due to the formation of some new polar groups on the surface of the treated films. Moreover, at higher exposure times, the total surface energy in all treated films increased while a reduction in contact angle occurred. The behavior of surface roughness in each sample was completely different at higher exposure times. 展开更多
关键词 plasma surface treatment biaxially oriented polypropylene polyvinyl chlo-ride poly methyl methacrylate) wettability
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Synthesis and Characterization of Novel Hybrid Poly(methyl methacrylate)/Iron Nanowires for Potential Hyperthemia Therapy 被引量:1
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作者 Huey-Wen Liou Hong-Ming Lin +5 位作者 Yeu-Kuang Hwu Wen-Chang Chen Wei-Jen Liou Li-Chung Lai Wei-Syuan Lin Wen-An Chiou 《Journal of Biomaterials and Nanobiotechnology》 2010年第1期50-60,共11页
Externally applied magnetic fields have been used in this study to fabricate bamboo-like iron nanowires with or without a layer of Poly(methyl methacrylate) (PMMA). The hybrid PMMA/Fe nanowires were synthesized via ha... Externally applied magnetic fields have been used in this study to fabricate bamboo-like iron nanowires with or without a layer of Poly(methyl methacrylate) (PMMA). The hybrid PMMA/Fe nanowires were synthesized via hard X-ray synchrotron radiation polymerization with various treatment parameters. The results of XRD show that an oxide layer formed on the surface of the iron nanowires. The Fe2O3 and Fe3O4 phases coexist in the iron nanowires without X-ray irradiation. After X-ray irradiation, the Fe2O3 phase transformed into Fe3O4, which stabilized the iron nanowires. The results of XAS proved this phase transformation. TGA analysis confirmed the thermal properties and solid contents in these specimens. Their ferromagnetic behaviors were examined by magnetic hysteresis measurement, which indicated that the magnetic and structural properties of the nanowires can be manipulated by irradiation treatment. This may lead to a novel synthesis for iron nanowires that can be used in high thermal efficiency hyperthermia therapy. 展开更多
关键词 IRON NANOWIRES poly(methyl methacrylate) HYBRID X-Ray Irradiation XAS Magnetic Materials
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Antibiotic-free antimicrobial poly (methyl methacrylate) bone cements:A state-of-the-art review 被引量:1
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作者 Gladius Lewis 《World Journal of Orthopedics》 2022年第4期339-353,共15页
Prosthetic joint infection(PJI)is the most serious complication following total joint arthroplasty,this being because it is associated with,among other things,high morbidity and low quality of life,is difficult to pre... Prosthetic joint infection(PJI)is the most serious complication following total joint arthroplasty,this being because it is associated with,among other things,high morbidity and low quality of life,is difficult to prevent,and is very challenging to treat/manage.The many shortcomings of antibiotic-loaded poly(methyl methacrylate)(PMMA)bone cement(ALBC)as an agent for preventing and treating/managing PJI are well-known.One is that microorganisms responsible for most PJI cases,such as methicillin-resistant S.aureus,have developed or are developing resistance to gentamicin sulfate,which is the antibiotic in the vast majority of approved ALBC brands.This has led to many research efforts to develop cements that do not contain gentamicin(or,for that matter,any antibiotic)but demonstrate excellent antimicrobial efficacy.There is a sizeable body of literature on these socalled“antibiotic-free antimicrobial”PMMA bone cements(AFAMBCs).The present work is a comprehensive and critical review of this body.In addition to summaries of key trends in results of characterization studies of AFAMBCs,the attractive features and shortcomings of the literature are highlighted.Shortcomings provide motivation for future work,with some ideas being formulation of a new generation of AFAMBCs by,example,adding a nanostructured material and/or an extract from a natural product to the powder and/or liquid of the basis cement,respectively. 展开更多
关键词 Periprosthetic joint infection poly(methyl methacrylate)bone cement Antibiotic-loaded poly(methyl methacrylate)bone cement bone cement Antibiotic-free antimicrobial poly(methyl methacrylate)bone cement bone cement
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PREPARATION AND MECHANICAL PROPERTIES OF POLY(METHYL METHACRYLATE)/ URETHANE ACRYLATE COPOLYMERS
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作者 陈大俊 《Journal of China Textile University(English Edition)》 EI CAS 1997年第1期22-27,共6页
The urethane acrylate(UA) was made of poly(tetramethylenc oxide), 4,4’-diphenylmethane diisocyanate, and 2-hydroxyethyl methacrylate. A series of poly(methyl methacrylate) / urethane acrylate copolymers was prepared ... The urethane acrylate(UA) was made of poly(tetramethylenc oxide), 4,4’-diphenylmethane diisocyanate, and 2-hydroxyethyl methacrylate. A series of poly(methyl methacrylate) / urethane acrylate copolymers was prepared by using a redox initiating system. The copolymers had cross linked structures and two-phase morphologies as indicated by the results of the dynamic mechanical measurement and swelling test. 展开更多
关键词 URETHANE ACRYLATE poly(methyl methacrylate) COpolyMERIZATION cross link.
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MECHANICAL PROPERTIES OF CARBON/GLASS FIBER REINFORCED POLY(METHYL METHACRYLATE)COMPOSITES
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作者 巫辉 赵建国 +1 位作者 雷家珩 李建宗 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1994年第3期26-32,共7页
Artificial bone, carbon/glass fiber reinforced PM-MA composites have been prepared by hot press moulding of pre-preg -which monofilments of CF and GF impregnated by MMA prepolymer. When the PMMA volume fraction in com... Artificial bone, carbon/glass fiber reinforced PM-MA composites have been prepared by hot press moulding of pre-preg -which monofilments of CF and GF impregnated by MMA prepolymer. When the PMMA volume fraction in com-posites is 50% > theoretical and experimental results show that strength and modules of these hybrid composites are in accord with 'rule of mixture'. The tensile and flexure strength are the lowest when the raletive volume fraction of carbon fiber in rein-forcements is 50%,SEM examinations further explained re-sults. 展开更多
关键词 carbon/glass fiber REINFORCED poly (methyl methacrylate) mechanical properties
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Synthesis and characterization of poly(methyl methacrylate-co-polyhedral oligomeric silsesquioxane)hybrid nanocomposites
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作者 Ben Hong Yang Hong Yao Xu +1 位作者 Cun Li Shan Yi Guang 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第8期960-962,共3页
A novel poly(methyl methacrylate-co-polyhedral oligomeric silsesquioxane) hybrid nanocomposite was synthesized by free radical polymerization and characterized by 1H NMR, 29Si NMR, and TGA technologies. Compared wit... A novel poly(methyl methacrylate-co-polyhedral oligomeric silsesquioxane) hybrid nanocomposite was synthesized by free radical polymerization and characterized by 1H NMR, 29Si NMR, and TGA technologies. Compared with PMMA homopolymer, the nanocomposite has better thermal stability. 展开更多
关键词 polymethyl methacrylate) polyhedral silsesquioxane Nanoeomposite
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Surface Perfluoroalkyl Chains Segregation: A Tool for Reducing Calcium Deposits in Medical Grade Poly(Methyl Methacrylate)
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作者 Baljit K. Ghatora Peter J. S. Foot +3 位作者 Stephen J. Barton Ravtej S. Thatti Antonio Papagni Luca Vaghi 《Journal of Biomaterials and Nanobiotechnology》 2017年第2期176-187,共12页
Intraocular lenses can be manufactured from a wide variety of polymers, but due to the lost cost associated with the use of Poly (methyl methacrylate) (PMMA), it is still the preferred material used in the developing ... Intraocular lenses can be manufactured from a wide variety of polymers, but due to the lost cost associated with the use of Poly (methyl methacrylate) (PMMA), it is still the preferred material used in the developing countries. However, a major drawback to its use is the build-up of calcium containing deposits that are formed on the intraocular lens over a period of time. In an attempt to hinder this deposition, surface modification of medical grade PMMA has been carried out using perfluoroalkyl chain (1,2,4-trifluoro-3-(C10F21CH2O)-7-(N,N)-dimethylaminoacridine) segregation. The segregation was explored using a 1% 1,2,4-trifluoro-3-(C10F21CH2O)-7-(N,N)-dimethyla-minoacridine in two methods: film casting and spin-coating, a thin film onto preformed PMMA discs. Both methods were compared against control PMMA to determine which method provided the best hindrance against calcium containing deposits when immersed in a simulated aqueous humour solution. Characterisation of the surface using scanning electron microscopy coupled with energy;dispersive x-ray analysis indicated that the surface segregation of perfluoroalkyl chains had hindered calcification in both methods. This pleminary research shows promising results of employing perfluoroalkyl chains in the surface segregation of biomaterials that can be employed in intraocular lenses. 展开更多
关键词 poly(methyl methacrylate) (pmma) PERFLUOROALKYL SEGREGATION Medical polymers Wettability CALCIUM DEPOSITS
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Photochemical kinetics for holographic grating formation in phenanthrenequinone doped poly (methyl methacrylate) photopolymer
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作者 王健 孙秀冬 +2 位作者 骆素华 姜永远 孟庆鑫 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第10期4326-4332,共7页
The photochemical kinetics of phenanthrenequinone (PQ) doped poly (methyl methacrylate) photopolymer in holographic recording was studied theoretically and experimentally. The diffusion of PQ molecules during holo... The photochemical kinetics of phenanthrenequinone (PQ) doped poly (methyl methacrylate) photopolymer in holographic recording was studied theoretically and experimentally. The diffusion of PQ molecules during holographic recording was negligible because of its small diffusion coefficient at room temperature. A photochemical reaction kinetics model of PQ/PMMA was established. The analytical expressions for the temporal variations of transmittance and diffraction efficiency were derived. By fitting the experimental curves, some parameters related with the polymer components were obtained by the proposed model, which can be used to analyze the photochemical process and will be helpful to the optimization of material preparation. 展开更多
关键词 phenanthrenequinone doped polymethyl methacrylate) photochemical reaction
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POLYMERIZATION OF METHYL METHACRYLATE CHIRAL LIGANDS
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作者 Bin YU Xue Chun LIN +2 位作者 Meng Xian DING Hui Zhen HU Fo Song WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第1期27-30,共4页
Methyl methacrylate was anionically polymerized in the presence of chiral ligands, e. g. (+)-DDB and (-)-Sp. The polymers thus formed were optically inactive due to the instability of the helical chain for the less bu... Methyl methacrylate was anionically polymerized in the presence of chiral ligands, e. g. (+)-DDB and (-)-Sp. The polymers thus formed were optically inactive due to the instability of the helical chain for the less bulky ester group. Isotactic poly(methyl methacrylate) was given when (+)-DDB was used, whereas, a syndiotactic polymer was formed in the presence of (-)-Sp. Accordingly, two different propagation mechanisms were postulated. 展开更多
关键词 DDB LI pmma polyMERIZATION OF methyl methacrylate CHIRAL LIGANDS
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Effect of catalyst on formation of poly(methyl methacrylate) brushes by surface initiated atom transfer radical polymerization
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作者 刘辉 周晚珠 +3 位作者 叶红齐 韩凯 侯世川 张欣悦 《Journal of Central South University》 SCIE EI CAS 2014年第8期3049-3056,共8页
Poly (methyl methacrylate) (PMMA) brushes were synthesized from silicon wafers via surface initiated atom transfer radical polymerization (SI-ATRP). Energy disperse spectroscopy (EDS) and atomic force microsco... Poly (methyl methacrylate) (PMMA) brushes were synthesized from silicon wafers via surface initiated atom transfer radical polymerization (SI-ATRP). Energy disperse spectroscopy (EDS) and atomic force microscopy (AFM) confirmed that PMMA brushes were successfully prepared on the silicon wafers, and the surface became more hydrophobic according to the contact angle of 69~. It is found that CuCI/1, 1, 4, 7, 10, 10-hexamethyl triethylenetetramine (HMTETA) system is more suitable than CuBr/N, N, N′, N″, N′″-pentamethyl diethylenetriamine (PMDETA) system to control the free radical polymerization of MMA in solution. Nevertheless, better control on the thickness of PMMA brushes was achieved in CuBr/PMDETA than in CuC1/HMTETA due to higher activity and better reversibility of the former system. 展开更多
关键词 poly methyl methacrylate) atom transfer radical polymerization silicon wafer CATALYST
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COMPATIBILITY IN POLYMER BLENDS OF POLY (VINYL ACETATE) AND POLY (METHYL METHACRYLATE)STUDIED BY NMR
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作者 宋默 戴莹坤 +2 位作者 胡澄 黄玉惠 丛广民 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1992年第2期176-179,共4页
Compatibility of poly (vinyl acetate) (PVAc) with poly (methyl methacrylate) (PMMA) mixtures has been studied by using nuclear magnetic relaxation, differential scanning calorimeter and small-angle X-ray scattering te... Compatibility of poly (vinyl acetate) (PVAc) with poly (methyl methacrylate) (PMMA) mixtures has been studied by using nuclear magnetic relaxation, differential scanning calorimeter and small-angle X-ray scattering techniques. The nuclear magnetic relaxation time T_1's were measured as a function of composition in blends of PMMA and PVAc prepared from chloroform solution. The results show that the system is miscible for casting from chloroform solution. 展开更多
关键词 polymer blends ~1H nuclear magnetic relaxation poly (vinyl acetate) poly (methyl methacrylate)
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The Effect of Direct Gas Fluorination on Medical Grade Poly(methyl methacrylate)
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作者 Baljit K. Ghatora Stephen J. Barton +1 位作者 Peter J. S. Foot Philip Miller Tate 《Open Journal of Organic Polymer Materials》 2014年第4期74-83,共10页
Medical-grade poly(methyl methacrylate) (PMMA) is extensively employed in the fabrication of a variety of medical implants, including intraocular lenses (IOLs). However, a postoperative complication that leads to the ... Medical-grade poly(methyl methacrylate) (PMMA) is extensively employed in the fabrication of a variety of medical implants, including intraocular lenses (IOLs). However, a postoperative complication that leads to the failure of the implanted intraocular lenses has been recently identified. This process, termed calcification, occurs when calcium-containing deposits accumulate on the surface of the IOL. In this study direct gas fluorination was used to modify the surface of PMMA in an attempt to increase the service lifetime of the material in optical applications. PMMA discs exposed to a 20% fluorine/nitrogen gas mixture for 24 h were compared with untreated PMMA discs serving as control samples. Over time, both surface-fluorinated and untreated PMMA samples immersed in a simulated aqueous humour solution (SAHS) (pH 7.4, 35°C) were used to carry out in vitro studies. Attenuated total refractive Infrared spectroscopy (ATR-IR) Scanning electron microscopy (SEM), coupled with Energy dispersive X-ray analysis (EDX), showed that calcium-containing surface deposits were less abundant on surface-fluorinated PMMA compared with the control samples, indicating that the fluorinated surface was acting as a barrier to the deposits. Gravimetric analysis data showed that the decreased rate of diffusion compared with that of a control sample was due to the fluorinated surface. 展开更多
关键词 poly(methyl methacrylate) (pmma) Surface FLUORINATION In VITRO Studies Simulated Aqueous HUMOUR Solution (SAHS) Medical polymers
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Grafted Deproteinized Natural Rubber as an Impact Modifier in Styrene-Methyl Methacrylate Copolymer Sheet
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作者 Narumol Kreua-ongarjnukool Pitchaoa Pittavavinai Surakit Tuampoemsab 《Journal of Chemistry and Chemical Engineering》 2012年第8期698-707,共10页
This research was studied to prepare styrene-methyl methacrylate copolymer sheet (S-co-MMA sheet) by using DPNR (deproteinized natural rubber) as an impact modifier. The DPNR was prepared by adding SDS (sodium do... This research was studied to prepare styrene-methyl methacrylate copolymer sheet (S-co-MMA sheet) by using DPNR (deproteinized natural rubber) as an impact modifier. The DPNR was prepared by adding SDS (sodium dodecyl sulfate) into the HANR (high-ammoniated natural rubber latex) and followed by centrifugation. It was found that DPNR was successfully prepared with the lowest nitrogeneous content about 0.034±0.01% w/w by adding SDS for 1.00 phr and centrifugation at 12,000 rpm. Then DPNR was grafted with styrene and methyl methacrylate (DPNR-g-S/MMA) obtained by emulsion polymerization. The effects of DPNR-g-S/MMA were studied by varied the amount of SDS and redox initiator. From this result the grafting efficiency DPNR-g-S/MMA was higher than that of NR-g-S/MMA. The DPNR-g-S/MMA was used as an impact modifier in S-co-MMA sheet. Furthermore, the appropriate quantities of styrene monomer and DPNR-g-S/MMA were also investigated. While DPNR-g-S/MMA was used as impact modifier in S-co-MMA sheet, the result was shown DPNR-g-S/MMA improve impact strength of S-co-MMA sheet. Scanning electron micrographs of S-co-MMA sheet with DPNR-g-S/MMA was found the smooth fracture surface. Thus impact strength of S-co-MMA/gDPNR sheet was high and physical properties of S-co-MMA/gDPNR sheet could be able to be accepted in industry. Concisely, DPNR-g-S/MMA can be used as an impact modifier in S-co-MMA sheet. 展开更多
关键词 DPNR-g-S/MMA polymethyl methacrylate) polySTYRENE s-co-MMA sheet.
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EFFECTS OF ω-ACRYLOYL POLY (ETHYLENE OXIDE) MACROMONOMER ON EMULSIFIER-FREE EMULSI0N COPOLYMERIZATION OF METHYL METHACRYLATE AND n-BUTYL ACRYLATE
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作者 郭天瑛 宋谋道 +2 位作者 周庆业 郝广杰 张邦华 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1998年第4期351-355,共5页
Well-defined nonionic hydrophilic ω-acryloyl poly(ethylene oxide) macro-monomer (PEO-A) has been prepared by living anionic polymerization of ethylene oxidewith diphenyl methyl potassium as the initiator and acryloyl... Well-defined nonionic hydrophilic ω-acryloyl poly(ethylene oxide) macro-monomer (PEO-A) has been prepared by living anionic polymerization of ethylene oxidewith diphenyl methyl potassium as the initiator and acryloyl chloride as the reaction termi-nating agent. The polymer was characterized by FTIR and SEC. The emulsifier-free emul-sion polymerization of methyl methacrylate (MMA) and n-butyl acrylate (BA) containingvarious concentrations of PEO-A was studied. In all cases stable emulsion coplymerizationsof MMA and BA were obtained. The stabilizing effect was found to be dependent on themolecular weight and the feed amount of the macromonomer. 展开更多
关键词 MACROMONOMER ω-Acryloyl poly(ethylene oxide) Emulsifier-free emulsion copolymerization methyl methacrylate-n-butyl acrylate copolymer
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Structure Characterization and Thermal Properties of PMMA/Montmorillonite Nanocomposites via Emulsion Polymerization 被引量:2
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作者 QUXiong-wei GUANTong-hua LIUGuo-dong WANGMei-ying ZHANGLiu-cheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第3期366-372,共7页
Montmorillonite(MMT) modified with sodium silicate can change the arrangement of its layers from edge-face and edge-edge to face-face. With the fine dispersion of the modified MMT in water,the cation-exchange reaction... Montmorillonite(MMT) modified with sodium silicate can change the arrangement of its layers from edge-face and edge-edge to face-face. With the fine dispersion of the modified MMT in water,the cation-exchange reaction was carried out with cetyltrimethyl ammonium bromide(CTAB) to obtain organo-montmorillonite(OMMT). As OMMT was uniformly dispersed in methyl methacrylate(MMA) monomer,PMMA/OMMT nanocomposites were formed via a common emulsion polymerization. The products were extracted with hot acetone and characterized by FTIR,molecular weight,X-ray diffraction(XRD),transmission electron microscopy(TEM),DSC and TGA. These results show that most of the OMMT layers have been exfoliated,while the thermal stability is increased obviously. By means of FTIR spectral analysis,the ratios of the macromolecular radicals′ termination of disproportionation patterns to combination are increased with the addition of OMMT. This result further confirms the increase of the thermal degradation temperatures and glass transition temperatures of the PMMA/OMMT nanocomposites. 展开更多
关键词 NANOCOMPOSITE Thermal property MONTMORILLONITE poly(methyl methacrylate)
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