Properties+of+Biodegradable+Polymers

Biopolymers have a number of similar traits that seem to be ubiquitous. They have high heat resistivity(Dupont Vespel 2011; Matkó and others 2005; NEC 2008), light weight (NEC 2008), resistance to chemicals(Dupont Vespel 2011), and low co-efficient of friction(Dupont Vespel 2011). These properties give them a great deal of versatility for usage. They can be used as an insulator for homes(Anonymous 2005b), drinking bottles, plastic bags(All Green Things 2008), and ball bearings(Dupont Vespel 2011). These products may optimise the above characteristics to their greatest efficiency for their individual uses.

Flame retardancy of biopolymers is based heavily on thermal stability of the polymer (Hendrickson and Connole 2004; Dine-Hart and Wright 1970). The main factors affecting thermal stability of the molecule are the molecular mass distribution and crystallisation. Degradation is caused the oxidation of the polymer group (Hendrickson and Connole 2004). The amount of branching in a molecule will tend to increase its ability to decompose. This is because a tertiary carbon radical is more stable than a secondary carbon radical and more stable than a primary carbon radical. Thermodynamics play a role in the degradation. The stability of the tertiary radical is what allows it to last long enough for the attack of the oxygen. Crystalisation plays a similar role (Hendrison and Connole 2004; Dine-Hart and Wright 1970). The more ordered the crystal the quicker it is for the radical oxidation of the molecule. When a polymer is less rigidly constructed it follows a more amorphous crystal structure, thus making the attack of the radical more diffcult.

Flame retardancy is also linked to the additives that may be added to the end product, such as ammonium polyphosphate(Matkó and others 2005). The flame retardancy with respect to addivtives can be linked to two main characteristics of the end product, its polyol character of polymer matrix and how the polyol plasticizer in the end matrix. The flame retardancy of these products is due to intermolecular forces. It is observed that effects of added groups including oxygen(Hribernik and others 2007; Kozłowskiy and Wladyka-Przbylak 2008; Matkó and others 2005), as well as the natural branching of the carbon back-bone of the polymer. The oxygens allow for hydrogen bonding between the molecules, making the polymers bind stronger, resulting in the high flame retardancey of the biopolymers.

This flame retardancy gives the polymer a great deal of uses, the main thought of as an insulator for homes (Anonymous 2005a; Matkó and others 2005). The flame retardancy would allow for a fire to spread at a much lower rate(Kozłowskiy and Wladyka-Przbylak 2008), thus allowing for a safer building. This flame retardancy is also crucial to its uses in industry(Dupont Vespel 2011) for obvious reasons.

The low co-efficient of friction may be due to small nano-particles of the polymer being embedded into the surface of the polymer(Darder, Colilla, Ruiz-Hizty ; Li and others 2001). It is theorized via scanning electron miscroscopy, that the nano-particles, due to their small size do not break down under friction. This means that a surface may slip along the surface of the polymer surface, without degrading the product, allowing for the use of a product with minimal lubrication(Dupont Vespel 2011).

The electrical insulation is shown in the structure of the polymer. Insulation is caused by the protection of conducting groups from interacting with one another. The polymer consists primarily of carbon-carbon single bonds, which give no chance for electrical insulation.

This property of the biopolymer gives the molecule a great use of a coating for wires(Dupont Vespel 2011). The wires are able to conduct their electricity with great efficiency, without losing any of it to the surrounding insulating material.

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