free site creation software

Poly Propylene 

Chemtrade Marketing, based in South Africa are import and export suppliers of PP Resin.

One of the wonderful, but confusing, things about PP is that there are several different grades of the same polymer and no two resins behave alike.
It’s versatile, light weight, low density and sustainable.

Send us a message or get your quote. 

The Three Main Grades of PP

PP is a semi-crystalline polymer that is hazy in its natural state due to the presence of crystals.

PP is generally characterized as having a higher stiffness at a lower density, resistance to higher temperatures, and an excellent strength to weight ratio.

The three main grades of PP resin allow for improvement of specific properties as determined by the composition of the polymer chain:

Homopolymer Polypropylene
Homopolymer PP can be considered the most ‘basic’ grade of PP resin. This grade of PP resin is more rigid and has good resistance to high temperatures, making it particularly suitable for high-heat applications such as hot fill and microwave applications or steam sterilization applications.
However, the tradeoff to this is lower impact resistance, particularly at low temperatures. For this reason homopolymer resins are not recommended for freezer applications or other applications where the material will undergo extremely low temperatures for an extended period of time.
Additional characteristics of this grade of PP resin include a high melting point leading to excellent stiffness, superior scratch resistance, and good chemical resistance against most inorganic acids, alkalis and salts. In addition, this grade of PP resin provides strong resistance to environmental stress cracking when in contact with alcohols, esters, detergents or polar hydrocarbons.
Random Copolymer Polypropylene
Random copolymer PP resins are created by modifying the polymer chain through the addition of random chains of ethylene among the PP units.
Due to the presence of ethylene, the rigidity characteristic of homopolymer resins is somewhat sacrificed, however, this results in improved impact strength and a softer feel.
Additional benefits to this include improved heat sealability, lower melting point, resistance to envitonmental stress cracking and improved clarity.
Random Copolymer PP resins also exhibit good chemical resistance against most inorganic acids, alkalis and salts.
Impact Copolymer Polypropylene (or Block Copolymer PP)
Similar to random copolymers, impact copolymer PP resins are derived through copolymerization with ethylene, but with this grade the ethylene content is much higher.
This results in a much tougher material with excellent impact strength even at low temperatures. For this reason, impact copolymer PP resins are particularly suitable for freezer and freezer-to-microwave applications.
In the past, using an impact copolymer came with a tradeoff on transparency as traditional impact copolymers could not be clarified, even through the use of additives.
Polypropylene is currently one of the fastest growing polymers. Much of this growth is attributed to polypropylene’s ability to displace conventional materials (wood, glass, metal) and other thermoplastics at lower cost. Polypropylene (PP) is a tough, rigid plastic and produced in a variety of molecular weights and crystallinities.
Polypropylene is made from the polymerization of propylene gas in the presence of a catalyst system, usually Ziegler-Natta or metallocene catalyst. Polymerization conditions (temperature, pressure and reactant concentrations) are set by the polymer grade to be produced.
Various production processes exist with some general similarities. They are taking place either in a gas-phase (fluidized bed or stirred reactor) or a liquid-phase process (slurry or solution). The gas-phase polymerization is economical and flexible and can accommodate a large variety of catalysts. It is the most common technology in modern polypropylene production plants.

1 Casino Road
Founders Hill
Modderfontein Estate
South Africa

Branch Office Address
Liberty Building
21 Aurora Drive
Kwa – Zulu Natal
South Africa

Johannesburg Tel : +27 10 009 6858
Durban Tel : +27 31 536 2552
Mobile : +27 71 013 8348
E-mail :

Privacy Policy
Terms And Conditions

We welcome feedback. Please shoot us a email and let us know what is on your mind.

Business Hours
Monday:      08:00 to 17:00
Tuesday:      08:00 to 17:00
Wednesday: 08:00 to 17:00
Thursday:     08:00 to 17:00
Friday:          08:00 to 17:00
Saturday:      Closed
Sunday:        Closed

Public Holidays: Closed