Self-healing coatings production

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. 

Can ends are stamped from sheets of precoated metal. These coatings need to be able to self heal after stamping and for this reason are usually solvent-based thermoplastic coatings. Production speeds for a typical B B line run into millions of units per day so application and cure times are measured in seconds with very hot (> 200°C) stoving temperatures. Most B B products are now of two-piece, as opposed to three-piece, design. The market for this type of container is more mature in the USA than in Europe. 

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