SSCC 4743 Material Chemistry Section 01

SSCC 4743 Material ChemistrySection 01Assignment topic : PLASTICGroup Members :

TEO HAO TINGWAN NOR SULAIKA BT WAN SALLEHWAN NORWAHIDA BT WAN ABD RAHIM

INTRODUCTIONGreek word : Plasticos, means to be able to be shaped or be moulded by heat.Plastic is a polymeric material which can be moulded into any shape.All plastics are polymers, but not all polymers are plastics. A polymer is a chemical compound formed by a chemical reaction in which two or more monomers are combined to form a repeating chains of structural units.

HISTORY OF PLASTICJohn Wesley Hyatt developed a cellulose derivative as the substitute for natural ivory for commercial products such as dental plates to mens collar in around 1860 [1]. In next few decades, Leo Hendricks Baekeland developed the first completely synthetic plastic, which sold under the name Bakelite.In 1920, a German chemist named Hermann Staudinger assumed that all plastics consist of a large molecules held together by a strong chemical bond. Many new products were designed such as Nylon(Lucite), Methyl methacrylate(Plexigas) and polytetrafluoroethylene(Teflon) Julian Hill discovered the application of nylon to produce silk thread fiber.In 1953, Karl Ziegler developed polyethylene and Giulio Natta developed polypropylene, which are the two common plastics used.

Manufacture of PlasticProduction of plastic can be divided into four categorizes:Acquiring the raw materialSynthesizing the basic polymerCompounding the polymer into a material that can be fabricatedMoulding or shaping the material into its final form.Additives in Plastic ManufactureChemical additives can be used in the production of plastics to achieve certain characteristics. These additives include: antioxidants to protect the polymer from degradation by ozone or oxygenultraviolet stabilizers to protect against weatheringlubricants to reduce friction problemsFlame retardantsantistaticTypes of PlasticThermosetThermoplasticThermoset Plastics can only be molded once and cannot be soften and deformed upon heating.Thermoplastics soften and deformed easily upon heating and can be bent easily.Improve the materials mechanism properties, enhanced chemical and heat resistance.Shrink-resistance and easy bendability.Non-recyclyableCost-effectiveMore resistant to high temperatureRecyclableEco-friendly manufacturingReshaping capabilitiesExamples : Bakelite used for electrical handles and switches.Melamine used for floor tiles and kitchen wares. Examples :PVC and Polythene used for toys and containnersDisposal of Plastic Degradation of polymers is induced by chemical factors which is corrosive chemicals such as ozone or the sulphur in agrochemicals. The effect of a solvent on the structure of the polymer material can be significant at times. Usually, a swelling stage precedes the dissolution process. Dissolution is impeded by the strong intermolecular interactions degradation and stabilization of polyethylene between macromolecules. Chemical recycling is known as a pathway to convert the plastic wastes to more usable and energy-dense materials such as gas fuel or fuel oil for the chemical industries. Improvement of PlasticIn 1945, Cogan and Quarles has successfully improved the plastic composition by introduction of water insoluble polyvinyl partial acetal resins to be used in adhesive and paints [2].A group of Japanese researcher has improved the moisture resistance of plastic encapsulated internal circuit by introduction of copper lead frame materials [3].Development and use of biodegradable polymers and water-soluble polymers serve as an alternative to replace plastic will bring more advantages than drawback [4]. Application of PlasticPacking

Lightest packaging material reduce transportation energy, decrease emissions and lower shipping costsreduce amount of waste generated.Food conservation and preservationprotects and preserves perishable food for longerreduce waste & use of preservatives while maintaining the taste and nutritional value of food.Safe and hygienicprotects against contaminationof foods and medicine prevent the spreading of germs during manufacture, distribution and display. tamper-proof closures provide additional protection & security, transparent packaging allows people to look at food without having to touch it, cutting down on bruising and other damage.

Building & Construction

Durable & corrosion resistanceInsulationHeat insulator, prevent leakages and allow householdsto saveenergywhile alsoreducing noise pollution.Cost efficiencyLesscost to produce and install, even in custom-made forms.Minimum operation and maintenanceEasy to be installed, operated and maintained. In the case of plastic pipes, their flexibility allows them to cope with soil movements.Examples : Insulator, Piping, Window frame and Interior design.

TransportationUsed as internal parts of a vehicleThe weight of a car can be reduced as plastic is lighter than metal. Therefore, the petroleum consumption can be reduced by 7.5%.Used as externally plastic:Durable, do not easily corrode and require little maintenanceAllow freedom of design & economical manufactureUsed as Internal plastics fittings:Dashboards, flooring, seats & facesMaintain attractive appearanceEasy to clean

ElectronicsResource-efficiencyPolymers can help store energy for longerInvisible resource efficiency takes place by design flexibility of plastic parts inside household equipmentExample : Lye container in washing machine, reduce water consumptionResistanceServe as electrical insulator, combined with resistance to mechanical shock and stress as well as flexibility & durabilityExamples: Cables, household appliance and smartphones

Medical and HealthcareUsed as capsules for drug:Tartaric acid-based polymer : gradually breaks down, slowly release active gradients over longer period of time.Used as hearing aidsConsist of numerous components - a microphone, a transmission device connected to a micro-computer worn on the body, a stimulator & an electrode carrier with 16 electrodes for 16 different frequency ranges.

Sports, Leisure and DesignUsed as sports footwear : running shoes that weight just a few grams yet provide the strength & supplenessUsed in racquets : Plastics are light and strong with excellent shock-absorbing systems.