Dyneon, a subsidiary of the multi-technology company 3M, has created a new melt modifier that significantly improves anti-dripping properties of thermoplastics. Its application in flame-retardant polymer compositions notably reduces production costs.
Dyneon™ polymer additives are used for two applications: for improving materials’ wear resistance and for enhancing anti-drip properties of flame-retardant formulations under high temperatures.
The latter line of products has been expanded with the newly developed Dyneon MM 5935 EF melt modifier. Standards for plastics used in electro and electronics industries, such as the American UL94 V-0 requires minimum dripping for thermoplastics during burning. The new melt modifier in combination with flame retardant additives make the material these reqirements. And Dyneon MM 5935 EF modifier meets requirements of the American UL94 V 0 standard even at lower concentrations. Like standard PTFE powders, the new polymer additive forms fibrils of 50 nm thickness under conditions of high shear. These stressed fibrils create a physical network frozen in the plastic. When the thermoplastic melts or burns, the fibrils relax which causes contraction and suppresses dripping. However, the new melt modifier has a number of advantages over common PTFE additives.
|3M corporation owns such registered trademarks as:
Post-it, Scotch, Scotchgard, Thinsulate, Scotch-Brite, Filtrete, Command, Dyneon. The company works with clients from 200 countries and has staff of 67 thousand people.
Dyneon is one of the leading suppliers of fluoropolymers and specialty additives.
Headquartered in Oakdale, Minnesota USA, the company has representative offices and production sites in 50 countries, including Russia. The company has more than 800 employees.
Although the new additive is also based on PTFE it utilizes a unique Dyneon technology to prevent the premature fibrillation that in conventional PTFE powders already begins at temperatures of 19 °C, having detrimental effect on their flowability and technological characteristics. The given powder-like modifier preserves its properties at even higher temperatures and doesn’t require cooling during storing and transportation. Even at production temperatures of up to 50 °C one has no need in providing lower temperatures for working with the material, thus reducing production costs.
Dyneon MM 5935 EF be used at lower concentrations and ensure better final product quality. This obvious advantage provides new opportunities for design and combining materials, particularly in extra thin-walled articles manufacture.
Characteristics of polpypropylene containing the new additive was tested, such as sagging behavior until breakage and the degree of shrink-back after the load was removed. The result was that a concentration as low as 0.2 weight percent of the new melt modifier was sufficient to prevent sagging. The same amount of the standard additives had virtually no beneficial effect on polymer characteristics. Conventional PTFE powders must be used in a concentration of at least 0.5 weight percent before they start to achieve only slight shrinkage. The same amount of the new polymer additive already shows an effect that is three times greater. At the higher concentration of 1.0 weight percent, Dyneon MM 5935 EF melt modifier achieves twice as much shrink-back as the same amount of conventional additives.
The new additive demonstrated better free-flowing characteristics then traditional PTFE ones and improves material rheological and technological properties. These enhanced free-flowing characteristics offer an excellent dispersion in compounds of ABS, PBT, PET, HIPS, PC, PE, PP and many other. Free-flowing Dyneon MM 5935 EF melt modifier flows into the extruder through standard feeder equipment without bridging or obstruction.