What is it?
This grade contains 25% post-consumer polystyrene (PCR PS) generated from waste of expanded polystyrene (EPS, or Styrofoam). The post-consumer waste is collected through drop-off locations and includes PS packaging: foam cups, plates, clamshell take-out containers, meat trays, egg cartons, and coolers. In addition to the drop-offs, the company is also associated with recycling centres that provide additional collection events on specific schedules and locations. The collected material was exclusively used in contact with food and is clean of organic waste.
No materials are collected from building or construction applications, as they may contain flame retardant additives.
The PCR PS is dissolved in styrene monomer and undergoes a series of purification steps to separate the polymer from additives and contaminants. The clean solution is then fed to the polymerization process; the result is a PS with a controlled content of recycled material.
Variations resulting from different waste feeds are neutralized during the polymerization process, resulting in a homogeneous quality in each batch.
Tensile Modulus (MPa): 2840
Tensile Strength (MPa): 46
Strain at break (%): 6,5
Density (kg/m³): 1.04
Melt Volume-Flow Rate (cm3/10min): 3.6
The mechanical and visual properties of this grade are very close to those of virgin polystyrene. It is easy to process, with a medium flow and good dimensional stability. It is nontoxic and also highly resistant to gamma radiation, which is necessary for sterilization when used for medical devices.
Look and feel
The material is transparent with a slight haze (>9 according to ASTM D1003) which makes it suitable for any application in which clarity and light transmission are key factors.
Resirene is conducting an LCA on this grade, and they estimate a 14% reduction of the GHG emissions if compared with virgin PS.
This grade is designed for extrusion, and it can be used for injection moulding applications as well, with the proper adjustments in temperature. The base material can be also used for foamed components. It has an FDA Rating: 21 CFR 177.1640, therefore can be used for food packaging and products in direct contact with food, as well as kitchen appliances.
Why we chose this material
Foamed polystyrene, especially one used for food packaging, is rarely recycled and usually ends up either incinerated or in landfills. This material presents not only a solution for a challenging recycling fraction but also a convincing grade in both its appearance and its properties. Looking at it, no one would notice it contains post-consumer recycled material.
Why you should consider this material
You are looking for a transparent material with recycled content.
You are looking for a food-grade recycled material.
About the manufacturer
Resirene has been manufacturing and marketing styrene polymers in Mexico since 1973, along with copolymers and specialty polymers.
The company recently added a chemical division to its portfolio, and Resirene is now part of Grupo KUO, a Mexican industrial conglomerate with 25 operating locations selling to over 70 countries.