What is RPSF, its manufacturing process, quality parameters and Why should we promote RPSF?

April 15, 2022

Our world is producing double the amount of plastic waste as it used to generate two decades ago, this results in a huge volume of plastic waste leaking into the environment and acres of landfills. According to a report published by OECD recently only 9% of plastic waste is recycled successfully and 22% is Mismanaged. According to the Material Recycling Association of India (MRAI), only 30% of waste was recycled in India in 2018, Which includes ferrous scrap, glass, paper, and plastic waste. With climate change, Heatwave and increasing pollution we need to find ways to make our planet a better place for the coming generation. Recycling is one of the most important steps to protect the environment and should be taught to the citizens of the world to contribute to it.

Recycling is changing the form of waste or scraped products into something useful. It can be done on different materials like ferrous scrap, glass, paper, and plastic waste. The world is moving so fast people like to use easily accessible materials which can be used and disposed of with minimum effort and cost. Plastic is one of the most used materials in the packaging industry. There is a variety of plastic that are used for different purposes accordingly. Some plastic can be recycled and some cannot, the Indian government is promoting the use of the kind of plastic which can be recycled instead of landing in dumps.

What is RPSF?

RPSF stands for Recycled Polyester staple fiber which is an artificial man-made fiber derived by recycling PET/Polyester scraps and used PET bottles. It is utilized in Insulation, filtration industries, Cushion, Pillows & Home Textiles, Non- Woven carpets, Artificial Fur Fibers, Scrub pads, automobiles, etc. Due to the good resilience properties shown by RPSF, they are used to make premium pillows, quilts, and cushions.

Manufacturing process

Its manufacturing process is described as follows:

  • Collection: First of all the PET bottles and scraps are collected from the waste segregator in bale form.
  • Segregation: The contamination like PVC, Iron, and stones are removed from the bale. This process is generally done manually.
  • Crushing and Cleaning: These collected bottles are then crushed into flakes of approximately 12-15mm and are cleaned thoroughly with a 2% of chemical solution namely Sodium Hydroxide (NaOH). This chemical cleaning helps remove dirt, stickers, and glue stuck on the flakes. The Maximum permitted contamination level is 200PPM
  • Drying: After the cleaning process the flakes need to be dried to remove the moisture acquired in the flakes. The flakes are put into a dryer and moved to a vacuum dryer where the flakes become soft and dried. During cleaning the flakes capture moisture within them which is known as inherent moisture. This moisture is reduced to less than 200 PPM by the vacuum dryer
  • Spinning: The dried flakes are moved to the extruder where the spinning takes place. The spinneret is used to make different PSFs either hollow or solid. The filaments which are produced during spinning are collected in bobbins or cans. These PSFs can be used to make Siliconized, harsh, conjugated, bouncy, and anti-static. The Cans or bobbins are taken to the creel area and combined and stretched many times in a chemical bath which results in fiber. The resultant fiber is relaxed and dried in a relaxer machine and bale packed in various lengths.

RPSF quality parameter

Various parameters in which the RPSF is characterized are:

  • Denier Size: This is used to measure the thickness of the fiber, the SI unit used to measure is den
  • Cut length: It is the length of the fiber and generally higher lengths are preferred, the SI unit used to measure is mm and cm
  • Feel: It can be of three types non-siliconized soft, siliconized or harsh feel Tensile
  • strength: It is the maximum limit of material up to which it can be stretched. The unit of measurement is gm/Denier
  • Elongation:It is the maximum limit of material up to which it can be stretched without damaging it permanently. It is measured in percentage
  • Oil Pickup: It is the amount of oil that is being sprayed on the fiber to provide more strength and a better finish. It is measured in percentage.
  • Crimps:Crimps are the waves formed in the yarn. From the PSF perspective crimps are the shortening of the length of yarn. It is Measured in cm
  • Shades: Colors of the yarn
  • Color Fastness: This term is used to define the resistance of the fabric towards fading or running. This has no unit
  • Quality: RPSF can be of different quality, Hollow Non-Conjugate and Conjugate Siliconised Fiber or Solid Fiber non-Siliconised/ Siliconised.

Why should we promote RPSF?

With the world shifting towards sustainability, we need to find ways that are better for the environment. Plastic is used almost everywhere, it's cheaper, durable, and easy to mold in different shapes and sizes. Having said that, as they say, everything comes with a price, and so is plastic, with all the benefits, it also has this major drawback of disposal. Since plastic is not a natural biodegradable material it is either put in landfills or in the ocean, leaking into the environment and in many countries just as litter. Recycling is the best way to save the environment from further damage.

RPSF is used in various industries and can be seen in some or the other products in our daily lives too. It can be seen in stuffed things like toys, Mattresses, cushions, and pillows, used for insulation purposes, production of nonwoven fabrics, and spinning yarns. Many brands are also promoting the use of RPSF and they make sure that they are following the global recycling standard (GRS) by using the GRS tags with their label. The GRS certificate is traceable too, it makes sure that the entire chain of producers are following it properly within the standard.

Apart from the benefits to the environment, RPSF has many properties which make it better than natural fibers. It is suitable for fabrics that are strain-resistant, wrinkle-free, fire retardant, etc. They are much more sturdy than a lot of natural fibers used in general. They have high elasticity and good abrasion resistance.