Effect of α- and β-Polymethyle Nenaphthalenesulfonate upon Properties of Cement Grout and Concrete

The following five oligomers of polymethylene naphthalenesulfonates with plasticizing properties of cement grouts were synthesized by the modified procedure. Condensation of sodium salt of α- and β-naphthalenesulfonic acid with formaldehyde in a ratio of 1- 1 leads to the formation of α-PNS-1 (2,7-polymethylenenaphthalene-α-sulfonate of sodium), and b-PNS-3 (5-7-polymethylenenaphthalene-b-sulfonate of sodium), increase of the ratio of 1- 3 - to trisubstituted cycle of α-PNS-2 (5-7,3-3-polymethylenenaphthalene-α- sulfonate of sodium), b-PNS-4 (5-7, 6-6-polymethylene-naphthalen-b-sulfonate of sodium), which modification leads to the formation of b,b¢-PNS-5 (b,b¢-PNS-5 4-4, 8-8-polymethylenenaphthalene-1,5-oxymethylene-2,6(β,β’)-disulphonate of sodium). Testing the synthesized additives on the plasticizing properties, on the strength and kinetics of the hardening cement grouts showed that PNS-1 by PNS-4 all proposed types of PNS increase the plasticity from P1 to P3 and in accordance with the State Standard 24211-2008 are plasticizers,increasing the concrete strength from 27 to 30%. PNS5 increases the plasticity from P1 to P5 and in accordance with the State Standard 24211-2008 are superplasticizer, increasing the concrete strength up to 60%.