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The contribution of the muscle to the specific heat of the body is approximately 47%, and the contribution of the fat and skin is approximately 24%. The specific heat of tissues range from ~0.7 kJ · kg−1 · °C−1 for tooth (enamel) to 4.2 kJ · kg−1 · °C−1 for eye (sclera). [13]
Polyethylene absorbs almost no water; the gas and water vapour permeability (only polar gases) is lower than for most plastics. Oxygen, carbon dioxide and flavorings, on the other hand, can pass it easily. Polyethylene burns slowly with a blue flame having a yellow tip and gives off an odour of paraffin (similar to candle flame). The material ...
HDPE is known for its high strength-to-density ratio. [4] The density of HDPE ranges from 930 to 970 kg/m 3. [5] Although the density of HDPE is only marginally higher than that of low-density polyethylene, HDPE has little branching, giving it stronger intermolecular forces and tensile strength (38 MPa versus 21 MPa) than LDPE. [6]
Low-density polyethylene (LDPE) is a thermoplastic made from the monomer ethylene. It was the first grade of polyethylene , produced in 1933 by John C. Swallow and M.W Perrin who were working for Imperial Chemical Industries (ICI) using a high pressure process via free radical polymerization . [ 1 ]
Medium-density polyethylene (MDPE) is a type of polyethylene defined by a density range of 0.926–0.940 g/cm 3. [1] It is less dense than HDPE, which is more common. MDPE can be produced by chromium/silica catalysts, Ziegler-Natta catalysts or metallocene catalysts. MDPE has good shock and drop resistance properties.
The term specific heat may also refer to the ratio between the specific heat capacities of a substance at a given temperature and of a reference substance at a reference temperature, such as water at 15 °C; [5] much in the fashion of specific gravity. Specific heat capacity is also related to other intensive measures of heat capacity with ...
LLDPE has penetrated almost all traditional markets for polyethylene; it is used for plastic bags and sheets (where it allows using lower thickness than comparable LDPE), plastic wrap, stretch wrap, pouches, toys, covers, lids, pipes, buckets and containers, covering of cables, geomembranes, [1] and mainly flexible tubing. In 2013, the world ...
Ultra-high-molecular-weight polyethylene (UHMWPE, UHMW) is a subset of the thermoplastic polyethylene. Also known as high-modulus polyethylene ( HMPE ), it has extremely long chains, with a molecular mass usually between 3.5 and 7.5 million amu . [ 1 ]