[the classification of polypropylene (PP) plastics]
Dosage of polypropylene is individual plastic range of all the biggest category, also is the most widely application scope, can make classification of different base material within the classification can still different melt flow rate of specifications, the individual may even need to add additional additives area again set USES the specification, such as: single polymer, MFR, 12 or so can be used for general injection products, also can produce multifilament fiber, more broad molecular weight distribution can be deliberately created to improve fiber weaving segment after machining; It can also add the lubricating agent and anti - phase viscosity to increase the opening of the plastic bag. Therefore, there are many specifications, but the general nature is similar, and there is an alternative to each other in addition to the purpose. This is an attempt to classify the different types of materials for reference and explain them one by one.
1. HOMOPOLYMER single polymer, which is called HOMOPOLYMER, is the raw material of pure propylene polymerization.
2. A single polymer with IMPACT COPOLYMER is used to add ethylene propylene rubber, and the IMPACT strength depends on the rubber content. The degree of cold tolerance is mainly seen in the content of ethylene. Each raw material manufacturer process is different, the highest ethylene content also is different.
3. RANDOM COPOLYMER (RANDOM COPOLYMER) is a RANDOM COPOLYMER, which is composed of propylene and ethylene COPOLYMER, and the ethylene is randomly dispersed in the polymer, which mainly reduces the crystallinity of the polymer and thus improves the transparency.
4. HIGH molecular acticity or HIGH CRYSTALLINITY reduces the content of the dislocation structure in PP polymers and increases the CRYSTALLINITY of the regular structure. It mainly improves the rigidity of raw material, heat and temperature, surface hardness, resistance and luster. Adding a nucleating agent, of course, will help enhance the above
Grade 5. Heat sealing (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%, the 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 properties so as to achieve the above requirements.
Grade 6. ALLOY (ALLOY) of different plastic raw materials high proportion of mixed level is ALLOY, such as PP add LDPE can improve flexibility and impact strength, also can reduce the necking on processing and increase smoothness, can also reduce falling in molding material. PP plus EPR plus HDPE can maintain rigidity, reduce the whitening phenomenon caused by high EPR content and improve the impact strength.
7. Composite materials (COMPOUNDING) means mixed composite materials with different materials, such as adding glass fiber, all kinds of inorganic mineral powder, wood powder, paper scraps or grains micro organic matter, to improve various properties in PP material. Mineral powder includes: talcum powder, calcium carbonate, barium sulfate, mica, carbon black, carbon fiber and bromide etc.
8. RUBBER (RUBBER) RUBBER, TPR (thermal plastic RUBBER), and TPE (hot plasticity elastomer), sometimes it's hard to boundary points, have all sorts of defined statement and, most of the RUBBER can be blended with PP, in addition to the series of EPR, it is hard to define or mixing is positioned in alloy composite material. General often blended with PP with EPR and EPDM rubber, suitable for direct mixing with PP production card have CATALLOY, PLASTOMER, ENGAGE, TAFMER, KRATON and SANTOPLENE, etc.
9. Special specifications (SPECIALS) before cover in similar can be classified as such, for example: High Melt Strength materials (HMS, High Melt Strength) can be used in foaming materials to improve surface air tightness foaming effect, also can reduce the plate forming drop phenomenon.