Feasibility study on bisphenol A as phenol replacement to produce aminosulfonate-phenol-formaldehyde superplasticizer for application in concrete

In this study, phenol was replaced by a powdery bisphenol A to produce aminosulfonate -phenol-formaldehyde (ASPF) superplasticizer (SP); ASPF SP and aminosulfonate-bisphenol A- formaldehyde (ASBF) SP were prepared. ASPF and ASBF SPs have -NH₂, -OH, -CH₂, -C₆H₅, -SO₃ functional groups, the weight-average molecular weight of 17.22 and 18.61 kDa, respectively, and the average polydispersity index of 1.08 and 1.53, respectively. The cement particle surface with ASPF SP has a higher initial zeta potential than that with ASBF SP. Along with time, the zeta potential of the cement particle surface with ASPF and ASBF SPs of 10 g/L change from -15.42 and -15.30 mV, respectively, in initial time, to -15.62 and -15.72 mV, respectively, after 120 min. ASPF SP exhibits a higher water reduction percentage than ASBF SP. The concrete with ASPF SP has a higher slump loss rate and mechanical properties than that with ASBF SP. The air content, wet density, and setting times of cement pastes with ASPF and ASBF SPs have no differences. It is an effective method to produce ASPF SP in a cleaner process.