## 2 Materials and Methods
### Methods
#### 2.2.3 Asphalt Binder Test Method  
The rolling thin film oven (RTFO) was used to quantify the volatiles lost (mass loss) during the short-term aging process of asphalt binder. Based on the Superpave Specification, the mass loss of asphalt binder should be less than 1 wt % to ensure the asphalt binder not to lose a significant number of volatiles over its life.  
The rotational viscometer was used to determine the viscosity of asphalt binders at high temperature. During the sample preparation, about 10.5 g asphalt binder is required for each sample, and spindle #27 was used in this test. This test measures the required torque value to maintain a constant rotational speed (20 rpm) of a cylindrical spindle under a constant temperature. The results were recorded in centpoises (cP) at one-minute intervals for a total of three readings.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Material Number** & **PECC** & **PECC-1 CA** & **PECC-2 CA** \\ \hline Zone 4 Temperature, \({}^{\circ}\)C & 220 & 215 & 215 \\ Zone 5 Temperature, \({}^{\circ}\)C & 220 & 220 & 215 \\ Zone 6 Temperature, \({}^{\circ}\)C & 220 & 220 & 215 \\ Zone 7 Temperature, \({}^{\circ}\)C & 220 & 220 & 215 \\ Zone 8 Temperature, \({}^{\circ}\)C & 220 & 220 & 215 \\ Zone 9 Temperature, \({}^{\circ}\)C & 220 & 220 & 215 \\ Zone 10 Temperature, \({}^{\circ}\)C & 220 & 220 & 220 \\ Die Type and Gap & 3 \(\times\) 3 mm & 3 \(\times\) 3 mm & 3 \(\times\) 3 mm \\ Pelletizer Setting at 8/Bath & H\({}_{2}\)O bath & H\({}_{2}\)O bath & H\({}_{2}\)O bath \\ Output Rate, lbs/h & 20 & 20 & 20 \\ \hline \hline \end{tabular}  
* Notes: (1) LLDPE and Ken-React\({}^{\oplus}\) CAPS\({}^{\mathrm{D}}\) L\({}^{\oplus}\) 12/L mixed in V cone blender for 4 min at 24 rpm in 2 lb batches and then placed in feeder 3. (2) Approximately 20 lbs of each extruded material was produced. (3) Feeder 3 helix: 0.5\({}^{\circ}\) open helix with end stub and 0.75” nozzle side discharge. (4) Feeder 3 Toshiba laptop feeder3_VectraA950 RX0.5 inopen0.75 insideddischargejak.par. (5) Feeder 2 helix: 0.75” open helix with 0.75” ID polyliner. (6) Feeder 2 NEC laptop Thermocarb file. (7) Extruder screw 5-14-05 design used from American Leistritz. Extruder screw cleaned in sand bath prior to use. (8) Purged with LLDPE at end of extrusion run to clean out extruder.  
\end{table}
Table 1: _Cont._In this study, the multiple stress creep recovery (MSCR) was conducted by introducing the RTFO aged asphalt binder specimen to the repeated creep and recovery process at high temperature. The test has been conducted in accordance with AASHTO TP 70-13 at 58 \({}^{\circ}\)C, which is the high temperature grade of selected asphalt binder, PG 58-28. The 25 mm diameter with 1 mm thickness circular disk-shaped asphalt binder sample was used. Two stress levels were introduced to the sample, which were 0.1 kPa and 3.2 kPa at one second loading time and nine seconds recovery time while performing the test [42; 43]. The test started with 0.1 kPa stress for ten cycles without time lags, and proceeded with 3.2 kPa stress under the same number of cycles. The new MSCR test, which is conducted based on AASHTO T 350-14, conducted 20 cycles 0.1 kPa stress loading and unloading. The MSCR test result may be different if conducted in accordance with AASHTON T 350 [44; 45].  
The bending beam rheometer (BBR) test was performed in accordance with AASHTO T 313; a simply supported beam of asphalt binder was subjected to a constant load of 980 mN for four minutes. The test was conducted at \(-12\)\({}^{\circ}\)C, \(-18\)\({}^{\circ}\)C and \(-24\)\({}^{\circ}\)C to define the critical cracking temperature of control and modified binders.