Polypropylene thread, also known as polypropylene or PP, is a synthetic fiber, transformed from 85% propylene, and used in a variety of applications. … The fiber is thermoplastic, resilient, light weight and resistant to mildew and many different chemicals.

Advantages of polypropylene Thread

  • Lower specific gravity/density (0.91 g/cm³) – More fibers/unit weight (~25% more).
  • More hydrophobic – absorbs less water and therefore dries faster.
  • Lower heat transfer – Retains more heat.
  • Inert to most chemicals.
  • Lower Cost than Polyester thread.

Polyester thread is a synthetic all-purpose thread. It is a good choice for most machine and hand sewing projects. Polyester thread works well with stretchy fabrics as it has much give to it. … Polyester is made to be stronger than most natural threads. It is important to avoid using polyester thread with natural fabric.

Advantages of Polyester Thread

  • Higher strength, tenacity and creep resistance – distinct advantage in Geotextiles and especially when load is on a fabric.
  • Greater yield per pound.
  • Higher melting point (260°C vs 165°C).
  • Withstands high temperature washing and drying.
  • More UV resistant – Retains strength and color better.
  • Resistant to most chemicals.
  • Strength higher than PP thread.
  • Has good abrasion resistance.
  • Polyester is used more for sewing – Higher strength and can withstand high temperatures generated during the sewing process (up to 350°C).
  • Polyester produces a better all-around fabric and sewing thread.