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Polycarbonate is commonly used in eye protection, as well as in other projectile-resistant viewing and lighting applications that would normally indicate the use of glass, but require much higher impact-resistance. Polycarbonate lenses also protect the eye from UV light.
A polycarbonate is an oxocarbon dianion consisting of a chain of carbonate units, where successive carbonyl groups are directly linked to each other by shared additional oxygen atoms. That is, they are the conjugate bases of polycarbonic acids , the conceptual anhydrides of carbonic acid , or polymers of carbon dioxide .
[34] [35] Additives are therefore one of the reasons why plastic is used so widely. [36] Plastics are composed of chains of polymers. Many different chemicals are used as plastic additives. A randomly chosen plastic product generally contains around 20 additives. The identities and concentrations of additives are generally not listed on ...
Polycarbonate plastic, which is formed from BPA, is used to make a variety of common products including baby and water bottles, sports equipment, medical and dental devices, dental fillings sealants, CDs and DVDs, household electronics, eyeglass lenses, [6] foundry castings, and the lining of water pipes. [9] BPA is also used in the synthesis ...
Poly(trimethylene carbonate) (PTMC) is an aliphatic polycarbonate synthesized from the 6-membered cyclic carbonate, trimethylene carbonate (1,3-propylene carbonate or 1,3-Dioxan-2-one). Trimethylene carbonate (TMC) is a colorless crystalline solid with melting point ranging between 45°C and 48 °C and boiling point at 255°C (at 760 mmHg).
Bisphenols A (BPA), F (BPF) and S (BPS) have been shown to be endocrine disruptors, potentially relating to adverse health effects. [3] [6] Due to its high production volumes, BPA has been characterised as a "pseudo-persistent" chemical, [7] leading to its spreading and potential accumulation in a variety of environmental matrices, even though it has a fairly short half-life.
The specific heat of the human body calculated from the measured values of individual tissues is 2.98 kJ · kg−1 · °C−1. This is 17% lower than the earlier wider used one based on non measured values of 3.47 kJ · kg−1· °C−1.
Plastination is a technique or process used in anatomy to preserve bodies or body parts, first developed by Gunther von Hagens in 1977. [1] The water and fat are replaced by certain plastics , yielding specimens that can be touched, do not smell or decay , and even retain most properties of the original sample.