# Phase Separation Study on the Storage of Technically Specification Natural Rubber Modified Bitumen
## 3 Results and Discussion
### Phase Separation Simulation of TSNR-Modified Asphalt
As the density decreased, the top viscosity decreased, indicating the accumulation of the TSNR phase with lighter density at the top as a result of phase separation [41; 42; 61]. According to the simulation results, the density and viscosity of the modified asphalt change significantly depending on storage time and temperature. It is concluded that the TSNR component added to the asphalt is incompatible. The asphalt and TSNR components were initially compatible, but after 12 h of storage, the TSNR component demonstrated incompatibility, resulting in phase separation. Many factors contributed to this, including the nonuniform particle size of TSNR, the significant differences in density and viscosity between the components, and the components' unpredictable mobility. Based on the simulation results, the density and viscosity of the modified asphalt vary significantly with storage time and temperature. We can conclude that the TSNR component added to the asphalt is incompatible. The asphalt and TSNR components initially demonstrated good compatibility, but after 12 h of storage, the TSNR component became incompatible, resulting in phase separation. Many factors contributed to this, including the nonuniform particle size of TSNR, the large differences in density and viscosity between the components, and the unpredictable movement of the components. Based on the research results described above, it can be used as a reference for making policy recommendations for related industries, such as the asphalt mixing plant (AMP), a user and producer of TSNR-modified asphalt. The AMP industry, which is engaged in hot mix production and modified asphalt production, really needs asphalt as a binder that has stable characteristics. However, simulation and experimental results show that the stability of TSNR-based modified asphalt is very poor at high temperatures for long storage times. This is a vital weakness and makes TSNR-modified asphalt difficult to accept and apply in the industry. However, it does not rule out the possibility that TSNR-modified asphalt can be applied in industry. This is due to the advantages of using TSNR-modified asphalt, which has the advantage of high adhesion and cohesion properties, increased durability in bearing loads, increased elastic properties of asphalt as a binder, a much higher softening point in suppressing rutting, and more compatibility with climate change. Based on this, TSNR-modified asphalt can be applied in industry by paying attention to several policy recommendations, which will be explained below based on simulation and experimental results:  
1. The TSNR-modified asphalt production process must pay attention to the particle size used, the melting temperature of the TSNR, and the mixing time between the asphalt components and TSNR. The TSNR particle size in the mixture must be maintained in the range of 100 to 150 nm; this is necessary to avoid increasing the number of maltene fractions, which can reduce the quality of asphalt in terms of its adhesion, cohesion, and elasticity properties. The particle size can be kept constant by paying attention to the melting temperature and mixing time. The optimum melting temperature for TSNR is 200 \({}^{\circ}\)C; higher temperatures can degrade some TSNR and will increase the number of maltene fractions in the modified asphalt mixture. Apart from that, the length of mixing time also influences the degradation of the TSNR phase. 2. It is recommended to store TSNR-modified asphalt at a temperature of 160 \({}^{\circ}\)C for only 12 h. This is considered necessary to avoid phase separation in TSNR-modified asphalt. Based on the simulation results, it was found that TSNR-modified asphalt can only be stored for 12 h, and longer storage causes coalescence and flocculation phenomena, which ultimately accelerate the phase separation. It is also recommended that the hot-mix manufacturing process uses TSNR-modified asphalt, which is stored at room temperature. 3.