Blow line blending

Pont de Nemours, Phillips, Celanese, and DuPont of Canada Ltd. The first were LDPE/HDPE blends, but later LLDPE/LDPE blending dominated the film-blowing application. Even a small amount of LDPE significantly improved LLDPE processability as well as the heat sealing, puncture resistance, tensile, and optical properties. However, for >35 % LLDPE in LDPE modification of film-blowing line was needed. Also LLDPE/LLDPE blends with broad MWD showed improved processability... 

Thermoformable foamed PP sheet that processes with the same drawdown, sag and cycle times as PS has been manufactured by Omam using new PP blends and Safoam carbon dioxide blowing agents from Reedy International. Oman has already produced monolayer PP sheet with a 40% density reduction and three layer sheet with a 50% density reduction. The trials have been carried out using blends of conventional PP and a new high melt strength PP grade developed by Montell. The Omam line used to produce the foamed PP sheet is conventional apart from... 

The SH plays a positive role in film blowing (15, 44) or in wire coating ( ). LPX-30 does not show this effect and Its processability Index Is low. On the other hand, SH of LDPE Is quite high and so Is the processability Index. The accepted mechanism for Improvement of fllm bubble stability Is self healing of a potentially weak spot by a local Increase of extenslonal viscosity caused by SH. It Is Important to note that adding to LPX-30 either 10 wtZ LDPE, 202 LLDPE-10 or lOZ LPX-24 was sufficient for generation of SH. The subsequent trial on a production line confirmed these results Increased bubble stability allowed for higher production rates of the blends. 

Eor facilitating film blowing of Z-N-LLDPE, the polymer may be blended with LDPE, known for its strong SH behavior. However, on conventional process lines, films fi om neat LLDPE are also being produced, but with considerable difficulties. Generally,... 

POM/TPU blends can be used in chain wheels, surfboard mast feet, switch buttons, clips for toys, car body part and fuel lines, blow moldings, and sports equipment. 

The 1 1 blends ate flexible, resistant to cracking under stress, show good water-vapor properties. The blends are formulated for extrusion, injection, and blow molding. Ute weld-line strength, resistance to warp e and shrinkage depend on processing conditions. ... 

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