| dc.description.abstract | Plastic waste remains an environmental menace around the world but more so in Sub-Saharan
Africa. In Kenya, recycling of plastics has been adopted notably for making fencing posts, and
this has been an object for job creation. However there is still a lot that needs to be done, bearing
in mind that a lot of plastic waste still litters the environment. A table top Injection moulding
machine was designed and fabricated to complement already existing efforts towards recycling.
In addition to the sound environmental management option this provides, it is hoped that the
machine could assist in job creation and more so at local individual levels where idle youths can
find an economic activity to engage in. Tensile specimens made from Virgin High Density
Polyethylene (HDPE) using the machine, were tested for Ultimate Tensile Strength (UTS) which
was found to have a value of 13 MPa and Modulus of Elasticity (E) which was found to have a
value of 0.9 GPa and the results are comparable to documented values which were 15 MPa and
0.8 GPa respectively. Recycled plastic was then added to the virgin plastic at various contents to
obtain an optimum processing point for the machine. These samples at varying contents of
recycled plastic were also subjected to tensile and three point bending test. The general
observation was that addition of recycled plastic to the virgin plastic improved tensile and shear
strength but declined the tensile modulus of elasticity. Addition of steel wires to the plastic at
60% recycled plastic content, improved tensile strength and modulus of elasticity. Compared to
other studies, it was observed that the material obtained could be suited for low strength car
bumpers. There is still room for further improvement work on this manually operated machine
but results obtained so far are promising as the machine can be used to produce small plastic
items such as pegs, complete toys or toy parts, beads and other small plastic items. | en_US |
