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How to Heat Treat Polycarbonate for Water Reduction

Polycarbonate is a type of plastic that exhibits high heat and electrical resistance. In addition, it's lightweight and stable. Polycarbonate is used in a variety of products, such as CDs, DVDs, automobiles, sports equipment, medical devices, tableware, reusable bottles and food storage containers. Polycarbonate can absorb up to 0.4% of water, causing damage to its physical properties. To decrease the absorption and retention of water, there are a few techniques that can be applied to polycarbonate pellets.

Things You'll Need

Polycarbonate pellets
Incubator

Instructions

- 1
  Predry the polycarbonate pellets in an incubator at 120 degrees C for four hours. The polycarbonate pellets contain moisture before they're placed into injection moulding for product production. Predrying the pellets will decrease the amount of moisture or water within the pellets. In addition, predrying the pellets will eliminate any foaming or splash marks created on the products from the moisture contained within the pellets.
- 2
  Add additives to the polycarbonate pellets. Additives decrease the resistance of polycarbonate against water. In other words, it decreases the absorption of water when the polycarbonate products need to be tested, such as in soap solutions. There are different types of additives that can be added to plastics to reduce the water retention, such as reinforcements, process aids, heat stabilizers, or fillers.
- 3
  Decrease the internal stress in the polycarbonate. Change your machine settings and moulding designs to create polycarbonate plastic that minimizes internal stress. The hydrolytic stability is decreased when internal stresses are present. A decrease in hydrolytic stability causes the molecular weight of the chemicals in the polycarbonate to decrease, resulting in poor performance and precipitation into the polycarbonate. Use polarized light to observe for internal stresses within the polycarbonate.

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