Processing Aids for PVC
Impact Modifiers for PVC are added to composite materials to improve the durability and toughness of plastic resins. In addition to impact performance, a number of other material characteristics such as optical and tensile properties, weatherability, processability, flammability, heat distortion and cost can also be improved by adding impact modifiers to PVC. One of the main applications of impact modifiers is in PVC resins: MBS (methyl butadiene styrene) and acrylics (impact modifiers) increase the impact resistance of PVC products without impairing other properties.
Impact resistance is one of the most critical properties in most plastics, especially styrenics, polyamides, PVC and thermosets. To solve this fragility problem, a mixture with a specific polymer or copolymerization with a monomer is usually carried out, generating a more flexible plastic material, which absorbs the impact generated energy and dissipates it in a non-destructive way.
The impact modification is somewhat complex, as it influences a lot other properties such as fluidity, gloss, elastic modulus, maximum processing temperature, etc. Other properties changes may not be linear and proportional to the amount of modifier incorporated in the polymer.