	US 12,135,310 B2
	Reference value quantification method for modifier dosage of modified asphalt
Bo Liang, Hunan (CN); Zhengchun Liu, Hunan (CN); and Jianlong Zheng, Hunan (CN)
Assigned to Changsha University of Science and Technology, Changsha (CN); and Central South University, Changsha (CN)
Appl. No. 17/413,629
Filed by Changsha University of Science and Technology, Hunan (CN); and Central South University, Hunan (CN)
PCT Filed Aug. 16, 2019, PCT No. PCT/CN2019/101149 § 371(c)(1), (2) Date Dec. 3, 2021, PCT Pub. No. WO2020/119166, PCT Pub. Date Jun. 18, 2020.
Claims priority of application No. 201811525955.3 (CN), filed on Dec. 13, 2018.
Prior Publication US 2022/0341873 A1, Oct. 27, 2022
Int. Cl. G01N 27/49 (2006.01); G01N 33/42 (2006.01); G16C 60/00 (2019.01)

CPC G01N 27/49 (2013.01) [G01N 33/42 (2013.01); G16C 60/00 (2019.02)]

6 Claims

1. A design reference value quantification method for a modifier dosage of modified asphalt, comprising the steps of:

(1) preparing a series of modified asphalt samples with different modifier dosages;

(2) determining an unsaturation degree of each modified asphalt sample by potentiometric titration;

(3) obtaining an inflection point of the unsaturation degree of the modified asphalt sample as a function of the modifier dosage by data fitting; and

(4) determining a reference value of the modifier dosage by the inflection point;

wherein step (1) is conducted as follows:

preparing a plurality of groups of tetrahydrofuran solutions of modified asphalt samples with different modifier dosages, wherein each group comprises the modified asphalt sample in an amount of 0.5-10 g, and the tetrahydrofuran in an amount of 55-100 mL; and

step (2) is conducted as follows:

S1, adding 10-30 mL of a 0.01-1 M Wijs reagent to each tetrahydrofuran solution of the modified asphalt sample, and reacting at 30-50° C. for 8-24 h; adding 5-30 mL of a 10-1,000 g/L potassium iodide solution, and reacting for 1-60 min, to obtain product solutions;

S2, titrating each product solution obtained in step S1 with a 0.1-2 M sodium thiosulfate solution, determining a titration end point by potentiometric titration, and recording a volume V₁of the sodium thiosulfate solution consumed, in mL;

S3, preparing a blank tetrahydrofuran solution, and repeating steps S1 and S2 to obtain a volume V₀of the sodium thiosulfate solution consumed by the titration of the blank tetrahydrofuran solution, in mL; and

S4, calculating the unsaturation degree Y of the modified asphalt sample according to formula (1);

wherein C refers to the concentration of sodium thiosulfate, in mol/L; 126.9 refers to the molar mass of iodine molecule, in g/mol; and W refers to the mass of the modified asphalt sample, in g.