The Optical Behavior of Polyethylene Spherulites

Polyethylene was crytallized from the molten film under temperature gradient. As a result, the optically positive spherulites were observed, though only the negative spherulites had been observed previOusly in polyethylene. When the radial structure units twisted regulary in a spherulite are formed parallel to the surface of the film, the spberulite is usually optically negative in polyethylene. In this study, the temperature gradient normal to the surface of the film gives so significant tilt of the radial structure units formed to the surface of the film that the radial refractive index becomes larger than the tangential one under the transmitted polarized light and the spherulites have optically positive behavior. The optical behaviors of the polyethylene spherulites and the crystallizing condition were studied and discussed

KAPASITAS LENTUR, TOUGHNESS, DAN STIFFNESS BALOK BETON BERSERAT POLYETHYLENE

Abstract The common problems of concrete are brittle failure and low of tension. Fiber reinforced plastic concrete is one of the alternatives to solve the problems. This research aim is to demonstrate a contribution of Polyethylene to revise the weakness of its properties. An experiment has been conducted to observe compressive strength, toughness, modulus of rupture and stiffness of fiber-polyethylene-reinforced concrete. The results show that by adding Polyethylene as a fiber in concrete material, compressive strength increases to 120.36%, moment capacity of beam increases to 115.79% and toughness increases to 318.6% compared with normal concrete. Hence, it can be stated that the addition of Polyethylene fiber has a significant contribution to increase the concrete performances. Keywords: concrete, fiber, polyethylene, stiffness, toughness

Method for casting polyethylene pipe

Short lengths of 7-cm ID polyethylene pipe are cast in a mold which has a core made of room-temperature-vulcanizable (RTV) silicone. Core expands during casting and shrinks on cooling to allow for contraction of the polyethylene

FDM preparation of bio-compatible UHMWPE polymer for artificial implant

Due to its properties of high wear, creep resistance, high stiffness and strength, Ultra-High Molecular Weight Polyethylene (UHMWPE) was developed to eliminate most metallic wear in artificial implant, which conventionally found in stainless steel, Cobalt Chromium (Co-Cr) and Titanium (Ti) alloys. UHMWPE has an ultra-high viscosity that renders continuous melt-state processes including one of the additive manufacturing processes, Fused Deposition Modeling (FDM) ineffective for making UHMWPE implant. Attempt to overcome this problem and adapting this material to FDM is by blending UHMWPE with other polyethylene including High Density Polyethylene (HDPE) and Polyethylene-Glycol (PEG) which provide adequate mechanical properties for biomedical application along with the improvement in extrudability. It was demonstrated that the inclusion of 60% HDPE fraction has improved the flowability of UHMWPE in MFI test and showing adequate thermal stability in TGA

Blends of linear-low-density polyethylene and thermoplastic bloodmeal using maleic anhydride grafted polyethylene as compatibilizer

Linear Low-Density Polyethylene (LLDPE) was blended with Novatein Thermoplastic from bloodmeal (NTP.) The compatibilizing effect of maleic anhydride grafted polyethylene (PE-g-MAH) on mechanical, morphology thermal properties and water absorption were studied and compared with blends without compatibilizer .The amount of polyethylene added was varied between 20% to 70% with 10% of compatibilizer. An improvement in compatibility between NTP and LLDPE was evident across the entire composition range only when using compatibilizer. The tensile strength of blends decreased over that pure LLDPE, but never dropped below that of pure NTP. Results showed that blending NTP with LLDPE decreased water absorption significantly, even more so using a compatibilizer. The result is a more water stable material

Penelitian Pengaruh Penggunaan Riklim Politilen Terhadap Sifat Ketahanan Pukul Dan Kekerasan

The aim of this research is to know further about the influence ot polyethylene reclaim to the characteristic of impact resistance and high density polyethylene (HDPE) compound.The research is done by making HDPE compound with the addition of polyethylene reclaim with various procentage of quantity.In fact the addition on of HDPE reclaim into pure HDPE doesn\u27t influence the hardness of the compound produced, but it influence the impact resistance to signification phase P 0,05 by linear aquation Y = 10,26 + 0,0887.The compound hardness is approximately 63,2 – 64,0 shore D, and impact resistance is approximately 10,83 – 18,91 kgcm/cm in various variation

Low temperature thermal expansivities of polyethylene, polypropylene and their mixtures

Low temperature measurements of length- temperature curves of polyethylene, polypropylene, mixtures of polyethylene and polypropylene, and copolymer

Shelf and cycle life evaluation of silver-zinc cells

Silver-zinc cells having a separator system of cross-linked high-density polyethylene with a methacrylic acid graft withstand corrosion when subjected to thermal sterilization treatments