What are the advantages and disadvantages of injection Moulding?
What are the Advantages and Disadvantages of Injection Moulding?
- Injection moulding is one of the most commonly used methods of producing identical plastic products in high volumes.
- 1) Fast production and highly efficient.
- 2) Low labour costs.
- 3) Design flexibility.
- 4) High-output production.
- 5) Large material choice.
What are the disadvantages of thermoplastics?
The primary disadvantage of using thermoplastics instead of materials such as metal is their relatively low melting point. Certain types of low-quality thermoplastics can melt when they’re exposed to the sun for extended periods.
Which of the following factors is not considered in a ram type injection Moulding?
Which of the following factors is not considered in a ram type injection molding? Explanation: Among the following, the inner pressure of the material, the outer pressure of the material as well as the mold and the temperature of the material and mold are important factors to be considered.
Why are thermosetting polymers preferred for some engineering products?
Thermosetting plastics are generally stronger than thermoplastic materials due to the three-dimensional network of bonds (crosslinking), and are also better suited to high-temperature applications up to the decomposition temperature since they keep their shape as strong covalent bonds between polymer chains cannot be …
What is thermoplastic example?
Examples of thermoplastic materials are polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyamides, polyesters, and polyurethanes. High-temperature thermoplastics include polyetherether ketones, liquid crystalline polymers, polysulfones, and polyphenylene sulfide.
What is the difference between Thermo and thermosetting polymers?
Thermosoftening (also called thermoplastics) are plastics which will soften when heated and can be reshaped. Thermosetting plastics are plastics do not soften on heating.
What is the meaning of thermoplastics?
Thermoplastics are defined as polymers that can be melted and recast almost indefinitely. They are molten when heated and harden upon cooling. Some of the most common types of thermoplastic are polypropylene, polyethylene, polyvinylchloride, polystyrene, polyethylenetheraphthalate and polycarbonate.
What are thermosetting polymers used for?
Common products and applications that are made from thermoset plastics include construction equipment panels, electrical housings and components, insulators, cell tower tops, heat shields, circuit breakers, agricultural feeding troughs, motor components, and disc brake pistons.
What are examples of thermosetting polymers?
Thermosetting plastics are also known as thermosets, thermosetting polymers, or thermosetting resins….Examples include:
- Bakelite (phenolic)
- Cyanate esters.
- Duroplast.
- Epoxy resin.
- Fiberglass (a fiber-reinforced thermoset)
- Melamine.
- Polyester resin.
- Polyurethane.
What are the properties of thermosetting polymers?
Thermosetting polymers are brittle and can only be formed once. They are hard to recycle. They are good insulators and are resistant to heat and chemicals.
What are the two main polymer synthesis reactions?
There are two general types of polymerization reactions: addition polymerization and condensation polymerization. In addition polymerization, the monomers add to one another in such a way that the polymer contains all the atoms of the starting monomers. Ethylene molecules are joined together in long chains.
What are the 2 types of polymers?
There are many types of polymers including synthetic and natural polymers.
What type of reaction occurs when a polymer of glucose is broken down?
Polymers are broken down into monomers in a process known as hydrolysis, which means “to split water,” a reaction in which a water molecule is used during the breakdown.
What are the two types of polymerization explain?
Polymerization Reactions The chemical reaction in which high molecular mass molecules are formed from monomers is known as polymerization. There are two basic types of polymerization, chain-reaction (or addition) and step-reaction (or condensation) polymerization.
What are the 3 main types of polymers?
From the utility point of view they can be classified into three main categories: thermoplastics, elastomers and synthetic fibers. They are commonly found in a variety of products worldwide. A wide variety of synthetic polymers are available with variations in main chain as well as side chains.
What is polymerization give an example?
Polymers are high-molecular-weight compounds, fashioned by the aggregation of many smaller molecules called monomers. An example of the first type of reaction is the union of thousands of ethylene molecules that gives polyethylene.
What is called polymerization?
Polymerization, any process in which relatively small molecules, called monomers, combine chemically to produce a very large chainlike or network molecule, called a polymer. The monomer molecules may be all alike, or they may represent two, three, or more different compounds.
What are the steps of polymerization?
The polymerization reaction consists of three stages: (1) initiation, (2) propagation, and (3) termination. Initiation occurs when the camphorquinones are promoted to a free radical state.
What are the classification of polymers?
The most common way of classifying polymers is to separate them into three groups – thermoplastics, thermosets, and elastomers. The thermoplastics can be divided into two types – those that are crystalline and those that are amorphous.
What is the importance of polymerization?
The formation of polymers, long-chain molecules made of repeating units of monomers (the essential building… Organic polymers play a crucial role in living things, providing basic structural materials and participating in vital life processes. For example, the solid parts of all plants are made up of polymers.
What are the uses of polymers in our daily life?
Polymers become the raw materials for products we now use every day, including: synthetic clothing, fiberglass, plastic bags, nylon bearing, polyethylene cups, epoxy glue, silicone heart valves, Teflon-coated cookware and our personal favorite, polymer based paints.
What are the importance of synthetic polymers in our life?
Synthetic fibres are important in our life because of multiple uses. Nylon is widely used in women’s hosiery and lingerie. It is used in carpeting materials and upholstery fabrics because it is easy to clean. The fabric is also used in life vests, umbrellas, sleeping bags and tents.
Why are synthetic polymers bad for the environment?
The non-biodegradable nature of synthetic polymers makes them a permanent waste. The used polymeric products like plastic bags and bottles cannot be dumped in sanitary landfills. These synthetic waste items are then combust in the incinerators which results in release of harmful gases and cause air pollution.
What are synthetic polymers?
Synthetic polymers are derived from petroleum oil, and made by scientists and engineers. Examples of synthetic polymers include nylon, polyethylene, polyester, Teflon, and epoxy. Natural polymers occur in nature and can be extracted. Examples of naturally occurring polymers are silk, wool, DNA, cellulose and proteins.
Which Fibre is stronger than cotton?
Repeat the same activity with threads of wool, silk and nylon. You will observe that the weight required to break the threads of wool, silk and^nylon is more than cotton. So, synthetic fibres are stronger than cotton.