Core tips: PP can be classified according to different substrates, in the classification can still be different melt flow rate specifications, and even according to the use of additives for individual commodities to determine the use of specifications.For example, in a single polymer, MFR: 12 or so can be used for general injection products, can also be used for the production of multifilament fibers, and can be specially manufactured to provide a wide molecular weight distribution to improve the back segment processability of fiber weaving.At the same time, it can also add sliding agent and anti-adhesive agent to increase the opening to meet the requirements of plastic bag products.
1. General level (Homopolymer)
Monopolymer, or homopolymer, is the raw material from which pure propylene is polymerized.
2. Impact COPOLYMER
When a single polymer is added with ethylene propylene rubber, the impact strength mainly depends on the rubber content, and the cold resistance mainly depends on the ethylene content.Different raw material manufacturers process different, the maximum ethylene content is also different.
3. High isotacites or HIGH CRYSTALLINITY
Reduce the content of dislocation structure in PP polymer, the relative increase of regular structure content, also improve the crystallinity.It mainly improves the rigidity, thermal denaturation temperature, surface hardness, scratch resistance and gloss of raw materials.Of course, the addition of nucleating agent will also contribute to the enhancement of the above properties.
4. Random COPOLYMER
Randomized copolymerization is propylene and ethylene copolymerization. Ethylene is irregularly dispersed in the polymer, which mainly reduces the crystallinity of the polymer and improves the transparency.
5. Terpolymer
Is an extension of the random of polymer, generally contains propylene ethylene (EPR) the highest levels at 3.5%, but there is also a process can be added to 5%, and higher ethylene content in product more soft, thermal deformation temperature, softening point, the lower the heat sealing temperature, sometimes in order to increase ethylene content with the aid of butadiene or other third ingredients become three common polymer, so as to achieve the above physical property requirements.
6. Alloy grade
The mixture of different plastic raw materials with a high proportion can be described as alloy grade. For example, PP added with LDPE can improve the softness and impact strength, and can also reduce the necking and increase the smoothness in processing. In molding, it can also reduce the drop material phenomenon.PP plus EPR plus HDPE can maintain rigidity, reduce the whitening phenomenon caused by high EPR content, and improve the impact strength.
7.Compounding
Mixing of different materials
Post time: Jun-18-2021