Q1: Pick out the correct combination about the role of various additives used in polymers.

ANS:C - Fillers: Does not affect the property of polymer but increases its weight.

The statement "Fillers: Does not affect the property of polymer but increases its weight" is not entirely accurate. Fillers are additives commonly used in polymers to modify their properties, and they can have various effects on the final properties of the polymer composite. Here's a more accurate explanation of the role of fillers in polymers:

1. Reinforcement: Fillers can significantly improve the mechanical properties of polymers by reinforcing them. For example, fillers like glass fibers, carbon fibers, or mineral powders (such as calcium carbonate or talc) can increase the stiffness, strength, and impact resistance of polymer composites. They act as a skeleton within the polymer matrix, providing structural integrity and preventing crack propagation.
2. Density and Weight: Fillers do increase the density and weight of polymer composites. Since fillers are typically denser than the polymer matrix, incorporating fillers into the polymer increases the overall density and weight of the composite material. However, this increase in weight is not the sole effect of fillers, as they also contribute to other properties.
3. Cost Reduction: Fillers are often used to reduce the cost of polymer materials by replacing a portion of expensive polymer resin with a less expensive filler material. This cost-saving strategy allows manufacturers to produce polymer composites with desirable properties at a lower cost.
4. Dimensional Stability: Fillers can improve the dimensional stability of polymers by reducing shrinkage and warping during processing and cooling. This is particularly important in applications where precise dimensional tolerances are required.
5. Electrical and Thermal Properties: Certain types of fillers, such as carbon black or metal powders, can enhance the electrical and thermal conductivity of polymers, making them suitable for applications in electronics, automotive, and aerospace industries.

Overall, fillers play a crucial role in modifying the properties of polymers, including mechanical, thermal, electrical, and dimensional characteristics. They are not merely inert additives that increase the weight of polymers but rather active components that can significantly enhance the performance and versatility of polymer materials.