Characteristics of Heterophase Radical Graft Polymerization of Methyl Methacrylate on Polymer Fibres

Pigment &Amp; Resin Technology

et al. 2010

PurposeThe purpose of this paper is to synthesise carboxymethylcellulose and methyl methacrylate graft copolymers (CMC‐g‐PMMA), which is used as an effective additive, for reinforcing the rice‐hull‐cement composite.Design/methodology/approachVarious CMC‐g‐PMMA copolymers were synthesised at different reaction temperatures, pH values of reaction solution and the dosages of monomer and initiator (potassium persulphate). The copolymers were characterised by Fourier transforms infrared (FT‐IR) spectra, thermal analysis (thermogravimetric and differential scanning calorimeter), X‐ray diffractometry (XRD) and scanning electron microscopy.FindingsAn optimal CMC‐g‐PMMA copolymer is obtained. For synthesis of the CMC‐g‐PMMA, the optimal reaction temperature is 80°C and pH value is 9. FT‐IR test of CMC‐g‐PMMA confirmed the existence of a chemical link between carboxymethylcellulose (CMC) and methyl methacrylate (MMA). The content of initiator has little effect on the reaction for synthesising the graft copolymer. Thermal analysis indicates the occurrence of graft reaction in CMC and MMA. XRD test proved that the chains of the graft copolymer can enlarge the proportion of the amorphous regions of CMC. Adding MMA has damage effect on the crystallisation.Research limitations/implicationsSince the results of this paper are obtained from the laboratory experiments, further research should be conducted for evaluating the performances of this copolymer in practical application.Practical implicationsThe mechanical test of the rice‐hull‐cement composite proved that CMC‐g‐PMMA is an effective additive for reinforcing the rice‐hull‐cement composite. The synthesis of CMC‐g‐PMMA provides a new alternative for modifying cellulose derivatives.Originality/valueThe CMC‐g‐PMMA obtained in this paper is a new kind of effective agent. It can reinforce the rice‐hull‐cement composite and expands the application of the composite in building industries.

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of carboxymethylcellulose and methyl methacrylate graft copolymers

Han

Shao

Pigment &Amp; Resin Technology

et al. 2010

“…It has been the subject of a great deal of research in recent times, mainly with respect to attempts to modify its physical and chemical structure as a means of improving its properties and broadening its industrial applications. Many investigators (Padma et al 1980;Canche-Escamilla et al 1997;Liu and Hsieh 2003;Bikkullova et al 2005;Mehmet and Temuz 2005) have reported modifications by means of the graft copolymerization of vinyl monomers onto cellulose, often using different initiator systems (Gupta and Sujata 2000;Pradeep et al 2004;Roman-Aguirre et al 2004). The properties of the grafted copolymers produced can then be tailored by the chemical structure of the monomers, the length of the grafted segment and the grafting parameters.…”

Section: Introductionmentioning

confidence: 99%

Preparation and characterization of graft copolymerization of ethyl acrylate onto hydroxypropyl methylcellulose in aqueous medium

2006

Cellulose

Graft copolymerization of ethyl acrylate (EA) onto water-soluble hydroxypropyl methylcellulose (HPMC) was investigated with potassium persulfate (KPS) as initiator in an aqueous medium. The effects of monomer concentration, initiator concentration, matrix concentration, reaction temperature, reaction time and pre-interacting time in terms of percentage of grafting (G) and grafting efficiency (G E ) are discussed. The graft copolymers were characterized by Fourier transform infrared spectra (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction analysis (XRD) and differential scanning calorimetry (DSC). In addition, equilibrium humidity adsorption behavior of the pure grafted copolymers was also studied.

“…Extensive investigations5–22 have been carried out to accomplish efficient graft copolymerization of various monomers onto cellulosic materials. Most of the works were concerned with chemical methods of grafting.…”

Section: Introductionmentioning

confidence: 99%

γ‐Radiation‐Induced Graft Copolymerization of Ethyl Acrylate onto Hydroxypropyl Methylcellulose

2006

Macro Materials & Eng

Summary: Graft copolymerization of EA onto water‐soluble HPMC was carried out using γ‐radiation using both simultaneous and preirradiation in an aqueous medium. The effects of radiation environment, radiation dose, monomer concentration, and reaction temperature on percentage of grafting (G) and grafting efficiency (GE) were investigated. For preirradiation, the observed values for G and GE were higher in air than in a nitrogen atmosphere. G and GE values are obviously higher for preirradiation; their maximum values were obtained for a radiation dose of 1.8 kGy. The grafting parameters increase for increasing monomer concentration up to 0.15 mol · L−1, where they reach their saturation values. In the case of preirradiation, the largest grafting parameters are obtained at 65 °C. The graft copolymers obtained were characterized by FTIR spectroscopy, TEM, SEM, and XRD methods. The method of irradiation significantly affects the mechanical properties of the grafted HPMC samples. Samples prepared by simultaneous irradiation show superior mechanical properties. In addition, the equilibrium humidity adsorption behaviors of the grafted copolymers were also studied, and the humidity resistance behavior of HPMC was enhanced through the grafting copolymerization.Transmission electron micrograph of the HPMC‐g‐PEA water dispersion.magnified imageTransmission electron micrograph of the HPMC‐g‐PEA water dispersion.