LLDPE (STRETCH FILM) related technical parameters

LLDPE (STRETCH FILM) related technical parametersLLDPE (STRETCH FILM) related technical parametersLLDPE production starting in the transition metal catalysts, in particular, Ziegler (Ziegler) or Philips (Phillips) type. Ene ring-based

Hydrocarbon derivative metal catalyst produced LLDPE new technology is another option. The actual polymerization in solution and gas phase reactor. In general,
Octene and ethylene in the solution phase reactor copolymer, butylene. Hexene and ethylene in the gas phase polymerization reactor. Generated in the gas phase reactor in the form of LLDPE resin particles
Type, and can be further processed into a powder or pellets for sale. With hexene and octene-based LLDPE by a new generation of super-Mobile, Union Carbide. Novacor and
Road plastics introduced. These materials have great toughness limit, remove the bags in the automatic application of a new potential. Very low density PE resin (density less than 0.
910g/cc. ) Also appeared in recent years. VLDPES flexible and soft with a degree is less than the LLDPE. Generally reflected in the characteristics of the resin melt index and density. Melt
Resin melt index reflects the average molecular weight and is mainly controlled by the reaction temperature. Average molecular weight and molecular weight distribution (MWD) has nothing to do. Impact of catalyst selection
MWD. Density by the comonomer concentration in the polyethylene chain in the decision. Comonomer concentration control the number of short branched-chain (its length depends on the comonomer type)
To control the resin density. Comonomer concentration the higher the density the lower the resin. In the structure, LLDPE in the number and type of branched-chain LDPE with different pressure
LDPE with long-chain branching, but only with a short linear branched LDPE. In the structure, LLDPE only in the number of short branched-chain with HDPE different. The number of HDPE over the short branched-chain
Less, therefore, there is a higher density of the material. Controlled physical properties of LLDPE on its molecular weight, MWD and density. LLDPE over LDPE, ultimately depends on
Its use. Typically, all applications using LLDPE production in more rigid products, although according to ATSM standards for low-density material, LLDPE and LDPE of density
Between the 0.91-0.925. The formation of higher LLDPE crystalline structure, because there is no long-chain branching. LLDPE larger crystalline products have high rigidity. This
Also a high degree of crystallinity compared with LDPE LLDPE, the melting point increased 10 ~ 15 ℃. Higher resistance to tensile strength, penetration resistance, tear resistance and elongation increase
LLDPE features, making it especially suitable for system STRETCH FILM. If instead of hexene or octene as a comonomer, butene even strength and tear resistance also impact the larger available
Improvements. For the same melt index and density of a given resin, hexene and octene LLDPE resins to improve impact and tear resistance to 300%. Hexene and octene
Longer side chains in the chain of the resin between the play as "knots" as the role of molecules, compounds improved toughness. Metal derivatives with cyclic olefin resin to catalyst production
Has a unique performance. Narrower MWD, comonomer distribution improved, with better transparency film, sealing, and impact strength, and the use of Ziegler catalysts such
Similar to the production of LLDPE. The characteristics of transparency, LLDPE and LDPE has similar shortcomings O LLDPE film turbidity and gloss is not good, mainly due to
For its higher crystallinity resulting film surface roughness. Transparency of LLDPE resin can be blended with a small amount of LDPE to improve.
     Processing: LDPE and LLDPE have excellent melt rheology, or flow. LLDPE has a smaller shear sensitivity, because it has a narrow molecular weight distribution and short
Branched-chain. In the shearing process (eg extrusion), LLDPE maintains greater viscosity, and thus the same melt index of LDPE than difficult to machine. In the extrusion, LLDPE
Lower sensitivity to shear stress relaxation of polymer chain faster, and the resulting physical properties of the blow-by than to change the sensitivity of an extension of the school in the melt, LLDPE
In a variety of strain rates generally have low viscosity. That it will not be the same as LDPE produce strain hardening in tension. Rate increases with the deformation of polyethylene
Plus. LDPE shows an alarming increase in the viscosity, which is caused by the entanglement of molecular chains. This phenomenon is not observed in LLDPE, LLDPE because of the lack of long-chain branching
The polymer does not tangle. Performance of the application of this very important film. Because LLDPE film, STRETCH FILM maintaining high strength and toughness in the next system call is easy thinner film.
Rheology of LLDPE
Can be summarized as "shear stiffness" and "extension when soft." When alternative LDPE LLDPE extruded at STRETCH FILM equipment and conditions must be modified. High viscosity of LLDPE
Extruder requires greater power. And provide a higher melt temperature and pressure. Model backlash from the mouth must be widened in order to avoid high back pressure and the resulting melt fracture and reduce production
Enough to use. LLDPE's unique requirements film bubble better ring to stabilize the wind lips. The internal cooling air ring with lips bubble bubble stability increased, while students in high
STRETCH FILM production rate increase production capacity. In addition to better cooling bubble, many STRETCH FILM production plant using blends with LDPE LLDPE melting method to enhance the truth, LLDPE
The extruded LDPE STRETCH FILM in existing equipment to complete, when LDPE LLDPE blends in the concentration of up to 50%. Process 100% LLDPE or rich
Blends of LLDPE and LDPE, the LDPE extruder using a general, necessary to improve equipment. According to the life of extruder, may be required to improve the mouth widening mode
Gap distance, improved air ring, modify the design to better screw extrusion, as necessary, increase the electrical power and torque. For injection molding applications, generally do not need to improve facilities, but the processing
Need to reach optimal conditions. Processing requirements of LLDPE rotational ground into uniform particles (35 mesh). Processing including powder LLDPE filled with mold, heating and biaxial
Gravitropism rotating mold to make LLDPE evenly distributed. After cooling, the product removed from the mold. STRETCH FILM,