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Can thermosetting polymers be Moulded?

Can thermosetting polymers be Moulded?

Thermosets, on the other hand, cannot be remelted—so while thermoplastic parts could, hypothetically, be ground up and used in a sandbag, their recyclability factor is limited.

What is the minimum pressure allowed to be given to the injection molding process?

The volume of material is not counted among important factors. 7. What is the minimum pressure allowed to be given to the injection molding process? Explanation: None.

Why thermosetting is suitable for compression Moulding?

It is very easy to change the material and colour. Therefore the compression moulding is ideal for small batch sizes. In combination with pressure and temperatures of 130 to 180° C, thermosets react as a chemical process, thus generating the high forces of resistance typical for this material.

What is the range of pressure for compression molding process?

A typical compression molding process is performed at a mold temperature of 350°F and mold pressure of 100 psi (180°C and 700 kPa) with curing time of 3 min. After the material is cured, the mold is opened and the plastic package is pushed out.

Is PVC a thermosetting polymer?

Plastics can be categorized as either thermosetting or thermoplastic. Polyvinyl chloride (PVC) is considered a thermoplastic. In comparison, thermosetting polymers form irreversible chemical bonds as they are cured and therefore they break down when heated and will not re-form as the temperature is cooled.

What is classified as thermosetting polymer?

Bakelite, a phenol-formaldehyde resin used in electrical insulators and plasticware. Duroplast, light but strong material, similar to Bakelite used for making car parts. Urea-formaldehyde foam used in plywood, particleboard and medium-density fibreboard. Melamine resin used on worktop surfaces.

Why are the plasticizers added with polymers?

Plasticizers are low molecular weight substances added to a polymer solution to promote its plasticity and flexibility. This is a temperature at which a polymer transforms from a hard, glassy material to a soft, rubbery material. Plasticizers lower the glass transition temperature of the polymers.

Why are the plasticisers added with polymers Mcq?

Explanation: Plasticizers are used to get the greater freedom of movement between the polymeric molecules. Plasticizers neutralise the intermolecular forces of attraction between polymer chains.

Which is another name for compression molding?

The mold is closed with a top force or plug member, pressure is applied to force the material into contact with all mold areas, while heat and pressure are maintained until the molding material has cured; this process is known as compression molding method and in case of rubber it is also known as ‘Vulcanisation’.

Which is an example of thermosetting polymer?

One of the most common examples of thermosets is bakelite which is relatively a bad conductor of electricity and heat. Some other examples of thermoset plastic polymers include silicones, vulcanized rubber, epoxies, polyesters and phenolics.