Low-density polyethylene

Low-density polyethylene (LDPE) is a thermoplastic made from the monomer ethylene. It was the first grade of polyethylene, produced in 1933 by Imperial Chemical Industries (ICI) using a high pressure process via free radical polymerization. Its manufacture employs the same method today. The EPA estimates 5.7% of LDPE (recycling number 4) is recycled. Despite competition from more modern polymers, LDPE continues to be an important plastic grade. In 2013 the worldwide LDPE market reached a volume of about US$33 billion.

Properties

LDPE is defined by a density range of 0.910–0.940 g/cm3. It is not reactive at room temperatures, except by strong oxidizing agents, and some solvents cause swelling. It can withstand temperatures of 80 °C continuously and 95 °C for a short time. Made in translucent or opaque variations, it is quite flexible, and tough but breakable.

LDPE has more branching (on about 2% of the carbon atoms) than HDPE, so its intermolecular forces (instantaneous-dipole induced-dipole attraction) are weaker, its tensile strength is lower, and its resilience is higher. Also, since its molecules are less tightly packed and less crystalline because of the side branches, its density is lower.

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In & Out

by: Loudboy

well i hate
my thoughts but
i think anyways
well i hate
my words but
i speak anyways
and i am calling
but you´re not there
so i i call back
but it´s too late
in & out and in & out
my mind is burning up with doubt
in & out and in & out
my heart is burning up with doubt
well i stare
at nothing
i´m blind to see
that i can´t
control my reality
and i am calling
but you´re not there
so i i call back
but its too late
in & out and in & out
my mind is burning up with doubt
in & out and in & out




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