for muslim: always follow the way of islam completely for non muslim: always set goal before working...

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FOR MUSLIM: ALWAYS FOLLOW THE WAY OF ISLAM COMPLETELY

FOR NON MUSLIM: ALWAYS SET GOAL BEFORE WORKING TOWARDS IT

ASSALAMUALAIKUM & GOOD MORNING

PLASTICS

TYPES OF PLASTIC

There are 2 types of plastic that is:a) Thermoplastics - A polymer that softens ans melts gradually when heated and it can be reshaped when still warm. b) Thermosets - A polymer that can’t be reshaped after manufacture

Thermoplastics

polyethylene, polypropylene, polystyrene & polyvinyl chloride (PVC) most common thermoplastics

Any object made from thermoplastic can be remolded into a new shape.

Thermoplastics creep considerably more than

thermosets, particularly at higher temperature Can be used for light structural properties

Polystyrene

has specific gravity of 1.05 It tensile strength is low, less than 48.5 MPa Modulus of Elasticity is low has good water resistance and dimensional

stability and inexpensive (cheap) But it possesses poor heat resistance, limited

weather resistance. It is brittle and lacks toughness

Pure polystyrene that is crystal clear used for storage container and cups.

Polystyrene and expanded polystyrene used

in tiles, packaging, containers, foams and

housewares. Foamed polystyrene used in poured-in-

place concrete wall systems & as insulation boards for foundation walls, masonry and wood walls and roofing.

Polystyrene Sheeting

In-situ concrete flooring on 300mm of Expanded Polystyrene insulation.

Polystyrene Block ( Usage In Construction )

Polyvinyl Chloride (PVC)

Specific gravity about 1.39 It’s made from monomer, vinyl chloride Tensile strength low nearly like polystyrene It’s an excellent insulator Used in raincoats and shower curtains Extensively used in floor tiles, electric

cables, flexible sheeting, hoses, pipes, expansion joint filler, ,moldings, luggage, decorative wall coverings,

Multi-Lock Industrial Warehouse Floor Tile Made Using PVC

PVC Vinyl Floor Tile

PVC pipe

Polyethylene

Specific gravity of 0.92 Tensile strength very low, less than 13.8

Mpa Modulus of Elasticity is very low It’s tough, weather-resisting plastic &

durable Has excellent electrical properties Has favorable chemical resistance

It’s common application is as polyethylene bags

Polyethylene used in manufacture of films, sheets, pipings, tanks, foams, electrical conduit and moldings.

Polyethylene films & sheets used as

dampproof courses, membranes & curing

membranes

Polyethylene Plastic

Polyethylene Bags

Product Made Using Polyethylene

Polypropylene

Has low specific gravity like polyethylene Low modulus of elasticity lightest material of all thermoplastics Has a higher softening point and shinier Good heat resistance but degrades under

exposure to sunlight Has good abrasion resistance and hardness Used for pipes, sheets, geomembranes

Polypropylene Sheets Protector Pack

Geomembranes Made Using Polypropylene

Polypropylene Pipe Fittings

Acrylics

Crystal clear in natural form has good weather resistance and ease of

forming Tensile strength higher than other

thermoplastic material Used in light fittings, skylights, screen

doors, paints and adhesives

Acrylic

Acrylic Shower Base, Screen and Door

Thermosets

Most popular thermosets are unsaturated polyester, epoxides, phenol-formaldehyde and polyurethane.

Polyester used in manufacture of fiberglass product and composite materials

Phenol-formaldehyde used in lavatory seats, electrical fittings and equipment decorative laminates.

Rope Made Using Polyester

Beaker Made Using Phenol Formaldehyde

                                                                                                                  

Advantages Of Plastic

It has high damping capacity ( ability to absorb part of the vibrational energy) that makes it suitable in application where vibration is encountered.

Excellent water resistant. - It have low water-absorption properties making suitable as impervious membrane layers that could prevent movement of water. Application in foundation, water supply installation, for concrete curing

It’s lower prices have contributed to the universal application of plastic. Low cost

Plastics have a favorable strength / weight ratio. It has low density (less than half of the concrete and 1/7 steel)

Since plastic is light, it present ease in handling, transportation, storage and assembly.

Most plastics are generally maintenance free and have good corrosion resistance

Thermal insulation of plastic is higher than other material. - used extensively as wall & ceiling insulation in both cast-in-place (as foamed insulation) and precast constructions (as rigid insulation)

Plastics can be molded to any shape and pattern. Plastic products come in variety of colors & textures.

- Manufactured plastics have good surface finish and may not require maintenance. - It’s availability in many color & texture makes it commonly used for floor, wall tiles & countertops.

Plastics can be manufactured with consistent quality.

Disadvantages Of Plastic

It has low stiffness and strength which make it can be used for load bearing construction

- It is subject to creep, that is the increase in deformation, under load, with time

- Rate of creep of plastic higher than concrete

- Creep deformation increases with stress level

- Therefore, plastics become dimensionally unstable under load.

Plastics are combustible/flammable material. Plastics emits toxic gases such as carbon

monoxide during burning. Plastics may emit dense smoke, thereby

making escape more difficult.

- Shouldn’t be used in exits areas of building such as around stairways and corridors

Expensive and subject to uncertainties arising for the oil price fluctuations.

Acoustical insulation of plastic is poor.

Modified Plastic

Addition substances can be added to the plastic during manufacturing process to improve the properties of the plastic.

Plasticizers to soften the plastic & make it easier for shaping.

Antioxidants prevent degradation by light and heat.

Colorants give color to plastic Fibers to improve strength of thermoplastic &

thermosets

Fiber Reinforced Plastic

For application requiring very high tensile strength Fibers added not only increase stiffness & strength

but also reduce shrinkage, improve abrasion resistance & provide dimensional stability to plastic resin.

This is a light weight, high strength & corrosion resistance material.

In civil engineering application for pedestrian

bridges, bridge repair and as prestressing tendons.

GOOD LUCK

ALWAYS SAY THANKS AS A SIGN OF APPRECIATION TO OTHERS WHO HELP YOU

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