*Production Technology
First of all, the compatibility between SBR and base asphalt: regardless of the shape of SBR, the key to production technology is to solve the problem of uniform dispersion of SBR in asphalt aggregation. If base asphalt and SBR have good compatibility, the ancient city of technology will be relatively simple and the production cost will be lower.At present, the technology adopted by several manufacturers in our country uses domestic asphalt as matrix asphalt, which can generally solve the dispersion problem of SBR modifier.The 5C ductility index of modified asphalt products can reflect the aggregation and dispersion of SBR in asphalt, which is also a landmark index of SBR modified asphalt.In general, the ductility of 5 degrees Celsius can reach more than 80 cm.
When using SBR block rubber, it is mainly to solve the problem of faster pulverizer delivery in front of it. If the pulverization effect is not good, it will directly affect the compatibility with the base asphalt and cause the production process to shut down due to blocked rubber block delivery.
When using SBR powder, the products with good powder level ( dry and storage are not easy to agglomerate themselves ) should be selected first. According to the actual situation of the reaction kettle, the appropriate conveying mode should be selected. If the powder conveying mode is not proper, the powder will agglomerate under the condition of high temperature and extrusion. In serious cases, the powder conveying channel will be blocked, and it will not be easy to disperse into asphalt after agglomeration. The SBR modified asphalt will also be blocked at the pipeline and pump inlet during conveying.
Secondly, toughness and viscosity toughness: toughness and viscosity toughness are two important technical indexes of SBR modified asphalt, which reflects that asphalt has viscoelasticity of polymer after SBR in asphalt.At the same time, the two indexes are also directly related to the performance of asphalt concrete.When our country first started to produce and use SBR modified asphalt in the past few years, it did not pay attention to these two indexes, because the technical specifications implemented did not impose requirements on product indexes and the analysis method was not mature.
In fact, the two indexes of products from several upstream factories have met the standard requirements.Since 2006, the western regions of our country have put forward requirements for these two indicators, but many production plants are still unable to meet the standards after process improvement.In order to solve this problem, SBR modifier should be added in the process.On the basis of a good dispersion process, the method of adding additives can also be adopted, so that SBR has a slight adhesive bond in asphalt, and SBR and asphalt can be combined more stably.
(Sourcing:network)
