Effect of zinc oxide level as activator on the mechanical properties of natural rubber composite

The effect of Zinc Oxide level as an activator on the Mechanical properties of Natural Rubber Composite was studied. It has been discovered that technicians usually add additional Zinc oxide different from the recommended dosage used in the formulation receipt during the process of compounding and also recovery of scorched compounds. One hundred parts per hundred rubber (100phr) of Natural rubber was compounded with Zinc Oxide levels of, 0, 2, 3, 4, 5, 6, 7, 8, 10phr respectively. The effect of Zinc Oxide level on tensile strength, elongation at break, modulus, hardness, abrasion resistance and compression set were investigated. The result obtained showed that as the Zinc Oxide level increased, the tensile strength, elongation at break, modulus, hardness and compression set attained their maximum values at 5.0phr, after which there was a gradual decrease of same properties as a result of reversion. For the purpose of hardness and enhanced tensile properties, a known quantity of 5.0phr is recommended.Keywords: Activator, Composite, Mechanical properties, Natural Rubber, Zinc Oxide

Effect of carbonization on the processing characteristics of rubber seed shell

The effect of carbonization on the processing characteristics of rubber seed shell powder was studied. Rubber seed shells were carbonized at different temperatures and then ground into fine powder. The various powders obtained were then characterized by pH, bulk density, moisture content, iodine adsorption value, yield%, conductivity and loss on ignition. The results show that there was a significant change in the pH as the heating temperature increases. The bulk density and moisture content decrease with increasing heating temperature while the iodine adsorption number and the loss on ignition increase with increasing heating temperature thus showing that carbonization has a significant influence on the processing characteristics of rubber seed shell

Graft copolymerization of acrylo–nitrile onto delignified native bamboo (Bambusa vulgaris) cellulosic and its utilization potential for heavy metal uptake from aqueous medium

Graft polymerization of acrylonitrile onto delingnified cellulosic material obtained from Nigeria grown bamboo (Bambusa vulgaris) could be initiated by a ceric ammonium nitrate redox system. Optimization of grafting of acrylonitrile onto cellulosic material was performed by varying the reaction conditions, such as the duration of soaking of cellulosic material in ceric ammonium nitrate solution, concentration of ceric ammonium nitrate solution, polymerization time, temperature of reaction, and acrylonitrile concentration and saponification time, in order to study their influence on percent grafting yield and grafting efficiency. The resulting cellulosic-g-polyacrylonitrile (PAN) copolymers were fractionated by extraction at 33 C with N,N’-dimethylformamide. Fractions were characterized by determining both the % add-on and the free polymer. Saponification of grafted copolymer was done by reaction with sodium hydroxide followed by methanol precipitation. The absorbent polymer so produced gave fair water retention values. The optimum reaction conditions obtained were: 20 mmol/L ceric ammonium nitrate solution in 1% nitric acid, soaking duration of 0.5 h at 40 C for a polymerization time of 2 h and saponification time of 3 h. The percent grafting was 167.89%, grafting efficiency was 93.52% and water retention value was 389 g/g. The grafting was confirmed using FTIR. Sorption of different metal ions in the mixture, e.g. Cr, Mn, Ni, Cu and Pb, by grafted cellulosic and the hydrogel was also investigated. Hydrolysis increases the sorption affinity of grafted cellulose toward water and metal ions

Polymer Applications in Agriculture

The use of polymer in agriculture is gaining popularity in science, particularly in the field of polymer chemistry. This has provided solutions to the problems of the present day agriculture which is to maximize land and water productivity without threatening the environment and the natural resources. Superabsorbent polymer hydrogels potentially influence soil permeability, density, structure, texture, evaporation and infiltration rates of water through the soils. Functionalized polymers were used to increase the efficiency of pesticides and herbicides, allowing lower doses to be used and to indirectly protect the environment by reducing pollution and clean-up existing pollutants. This account; a detailed review study, has been put together as an expose on the myriad application of polymer in the field of agriculture, highlighting present research trend , impact on food security and future outlook