Grafting of Maleic Anhydride onto Cyclized Natural Rubber by Reactive Processing: the Effect of Time and Rotor Speeds

Grafting of maleic anhydride onto cyclized natural rubber has been performed in an Internal Mixer with variation of time and rotor speeds. The grafted product were analyzed by Fourier Transformed Infra Red to determine the presence of Maleic Anhydride onto Cyclized Natural Rubber, and Thermographymetric Analysis to investigate its thermal properties. Fourier Transformed Infra Red spectra confirmed that the grafted product accured by appearance of characteristic band at 1780 cm-1. The optimum time of grafting process was 8 minutes, by means of carbonyl index. The rotor speeds were not significantly effected the grafting degree. Characterization by Thermographymetric Analysis observed that the thermal properties of grafted product were not significantly different from cyclized natural rubber standard. Keywords: grafting, cyclized natural rubber, maleic anhydride, time and rotor spee

Grafting of Maleic Anhydride onto Cyclized Natural Rubber by Reactive Processing: the Effect of Maleic Anhydride Concentrations

Grafting of Maleic Anhydride onto Cyclized Natural Rubber has been performed in the Internal Mixer at 150oC and 80 rpm. The grafted product were analysed by Fourier Transformed Infra Red to determine the presence of Maleic Anhydride onto Cyclized Natural Rubber and Differential Scanning Chalorimetry and Thermogravimetric Analysis to investigated their thermal properties. Fourier Transformed Infra Red spectra confirmed that the grafted product accured by appearance of characteristic band at 1720 cm-1. The higher concentration of Maleic Anhydride reacted the higher of grafting degree of Maleic Anhydride by means of carbonyl index. Futhermore, the glass transition temperature values increase with increasing the grafting degree of Maleic Anhydride and Thermogravimetric Analysis thermogram showed the thermal properties of grafted product did not change significantly compared with the Cyclized Natural Rubber blank. Keywords: grafting, cyclized natural rubber, reactive processing, maleic anhydrid

Field trial for assessment of avian influenza vaccination effectiveness in Indonesia

The aim of this field study was to determine the efficacy of vaccination against highly pathogenic avian influenza (HPAI) virus strain H5N1 in Indonesia. A limited, prototype clinical trial was performed using a standardised treatment group, in which poultry flocks were vaccinated at least twice with a selected H5N1 vaccine, and a control group comprising flocks treated with nonstandardised procedures chosen by the farmer. Each group consisted of six flocks comprising either layers or native chickens. Haemagglutination inhibition (HI) antibody levels were determined by regular serum sampling, and outbreak surveillance relied on non-Al-vaccinated sentinel birds. After three vaccinations high antibody titres were produced in the treatment group, and the percentage of layers with an HI titre > 40 was approximately 90%. Although no conclusions can be drawn regarding reduction of virus transmission, this study demonstrated that 11 farms remained free from Al during the observation period, and that a surveillance programme based on differentiating infected from vaccinated animals (DIVA) can be implemented