'Bio-Polymer Chemistry Assessment Task\r'

' business of Materials: Chemistry Assessment Task Part A: Biopolymers Definition: The term â€Å"Biopolymer” refers to polymers that are defecated by active electric organisms. Since these are polymers, biopolymers contain monomeric units that are covalently bonded to form bigger sructures. Biopolmers are divided up into 3 principal(prenominal) classes. These are: Polynucleotides (which include RNA and DNA), Polypeptides ( short polymers of amino acids) and Polysaccharides. Ex antiophthalmic factorles of some Biopolymers include: Cellulose, Starch and Proteins. point of reference: http://en. wikipedia. org/wiki/Biopolymer#Polypeptides Biopolymer: Polylactic acidFormation: PLA is produced from a renew qualified source. For example corn. Corn is harvested and then svelte to extract the starch from the raw materials. From the starch, grape sugar is produced. The dextrose is then fermented, transforming into lactic acid. The lactic acid is neutered into a polymer by the process of condensation, then forming yen chain molecular compounds into polylactic acid. The organism is Lactic Acid. Source: http://www. hitachi-pt. com/products/ip/process/pla. html Properties and Uses: Being able to bring down into lactic acid, PLA is used as health check implants in the form of screws, pins, rods and as a mesh.PLA tail also be used as a compostable packaging material. Cups and Bags have been made out of PLA. In the form of film, PLA shrinks upon heating allowing it to be used in shrink tunnels. PLA is also useful for producing loose-fill packaging, compost bags and liquid tableware. PLA chiffonier also be used in treatment in the body. Depending on the exact symbol used, it breaks down in the body within 6 months to 2 years. This degredation is desirable for a support building because it gradually transfers the load to the body as the organ heals.Source: http://en. wikipedia. org/wiki/Polylactic_acid#Manufacturers Assessment: The impact of PLA on the so ciety is that callable to the high demand or PLA products from resources such as corn, corn growers have been tampering with the genes of the corn to produce higher yields in order to suffice the demand. still though PLA is biodegradable it still dumbfounds at least three months in a controlled environment to decent break down into it’s components. However it is estimated to take 100 to 1000 years to decompose in landfill.PLA is also from a different origin than symmetrical plastics, therefore it needs to be kept pause when recycling. PLA is an alternative to the common plastic bag or plastic cup since it can be recycled which can be useful to the society. Source: http://www. scientificamerican. com/article. cfm? id=environmental-impact-of-corn-based-plastics Judgement: until now though PLA is an alternative to common plastic due to it being recyclable and biodegradable, PLA still needs to be refined to make it more efficient to produce, be cost effective and to be ab le to degrade at a much faster rate.Part B: Batteries Sources: Vertex learnedness Centre: Book, HSC chemistry, Vertex Learning Centre: Book, Production of Materials Section 6 and 7 Button Cell Plastic seal coat case Graphite rod Electrolyte Negative term Positive perch Plastic seal zinc case Graphite rod Electrolyte Negative terminal Positive terminal Leclanche Cell (Dry Cell) Sources: http://www. comf-hk. com/zcart/index. php? main_page=page&id=3&chapter=1 Leclanche Cell diagram- 4. 6 cells and batteries word document By Bernard Broekhuizen\r\n'