Significant reduction in the viscosity of polychloroprene rubbers provided by Lanxess
Monday, July 8, 2013
Leverkusen, Germany - In the new Baypren High Performance grades Baypren HP M010 VP and Baypren HP M210 VP, specialty chemicals company LANXESS is introducing two new polychloroprene grades with especially good flow properties that re-define the previously recognized lower limit for the viscosity of these rubbers. Both new low-Mooney grades are suitable for profile extrusion, for example, and, with their increased flowability, can help to significantly boost the cost-effectiveness of this process in the production of Baypren articles. “In the rubber industry, polychloroprene is considered to be an exceptionally versatile synthetic rubber,” says Dr. Klaus Zander, head of Global Marketing Baypren at synthetic rubber pioneer LANXESS. “However, over the years there have been repeated calls for polychloroprene variants with better flow qualities. Due to the processing requirements of the conventional compounding method, however, there has always been a lower viscosity limit that one could not go below.” Nonetheless, LANXESS has now achieved this. “Our new production process allows us to create Baypren grades with entirely new characteristics,” says Zander. “Consequently, several of the limitations of the previous compounding technology no longer apply. As one result, we are now finally able to provide our customers with low-Mooney Baypren grades.” Of the first two of these new particularly free-flowing additions to the LANXESS Baypren family, one grade (Baypren HP M010 VP) crystallizes slowly and the other (Baypren HP M210 VP) moderately fast. Their Mooney viscosity (ML (1+4) 100 °C) is around 28 MU. By way of comparison, Baypren 210, a conventionally compounded grade that is comparable to Baypren HP M210 VP, features a Mooney viscosity range of 39-52 MU. “The lower limit of what was previously possible lay at around 35 MU,” says Urban Dinges, head of Global Technical Marketing. “The leap to 28 is huge!” The lower viscosity of the new Baypren grades is noticeable in extrusion, for example. In laboratory testing, significantly higher volume throughputs were achieved with Baypren HP M210 VP, for instance. This should enable increased cost-effectiveness in profile extrusion. “At the same time, the energy required for extrusion is reduced,” says Dinges. Using Baypren HP M210 VP and M010 VP could also reduce the use of plasticizers, which can have a positive impact on product quality. Baypren HP M210 VP also performed excellently in terms of die swell. On the other hand, Baypren HP M210 VP and Baypren HP M010 VP specimens displayed strikingly similar results when it came to the physical properties of the vulcanizates. “In terms of tensile strength and hardness, the two new Baypren variants are on a par with their tried-and-tested stablemates with significantly higher viscosity,” explains Dinges. “The new grades are also impressive when combined with higher-viscosity polychloroprene.” LANXESS currently expects industrial-scale production to begin in Dormagen at the end of 2013.