THE CONCEPT OF THE STUDY 1. Silica-alumina + polymer alloy ¡ú no reaction ( polar ) ( non-polar ) Si O4-AlO4 + CH2 = CH2 ¡ú no reaction 2. Surface treatment ( addition of coupling agents ) O3Si-O- AlO3 + H3C-( CH2 )3 ¨CN- ( CH2 )3-Si ( OCH3)3 + CH2 = CH2 ¡ú O3Si-O-AlO3 ¡ú ©¦
Si ( OCH3 )3 + H3- ( CH3 )3 ¨C N-( CH3 )3 CH2CH3 3
Matrix modification ( grafting polymers )
CH3= CHCH3 + C4H3O2 + SiO4-AlO4 ( PP ) + maleic anhydride
¡ú CH2CHCH3-O-C4H3O2SiO3-AlO4 composites
The available unpaired electrons of oxygen reacts with tri-methoxy ssilicon, therefore, chemical bonding occurs. The organophilic nitrogen will bond with polymer.
Under alloying of polymers, the properties of many plastics can be greatly modified by alloying two or more polymers. The term is often used interchangeably and technically : blend is a mixture that are not fully compatible and alloys are mixture that are fully compatible such as polyethylene oxide and polystyrene. The blend appears as a separate phase when viewed under the microscope. These combinations are taking over on an increasing share of the market because it is easier to develop desirable properties by mixing known plastics than creating new ones ( Hydrocarbon Process, Modern Plastics, pp, 1981/82 )
One of the problems associated with blends and alloys is how to make the components bond together. The technique is to introduce compatibilizer which creates
interpenetrating polymer network by providing a physical bond between semi-compatible material. Most compatibilizers are block polymers and they produce an interwoven matrix of physically inseparable by chemically distinct polymers.
Conceptual Process
The concept stems from the idea of surface treatment and modification ¨C that is ¨C composites or polyblends are produced by alloying two or more chemically distinct and insoluble phase whose properties and structural performance are better than those components acting independently.
The process starts from surface treatment of additives and polymers that are to be used by introducing a coupling agents, an interfacial agent, than by grafting the polymer with compatibilizers by reactive-reaction of matrix using kneading process and finally molding the composites into its desired shape.
Proposed Equipment and Machines
Production Equipment: Super-mixer, cooling blender, kneader, crusher, twin-screw extruder, water trough, pelletizer, mold, vacuum sizing, hand-off machine, and cutting machines.
Laboratory equipment: Two-roll mill, hydraulic press, moisture tester, weighing scale, Brabender, spatula, beaker, molding plates, melt flow index tester, HDT/Vicat tester
Proposed Evaluation Strategy: Characterization of polymer and plastics additives , blank tests, modification of process design, set-up methodology within specified parameters, conduct physical and mechanical tests of blend and finished products, conduct biodegradation test of lineals. Compare results of experiments with those of of conventional products. Study the effects of biodegradable additives on physical and mechanical properties of plastic lumber.