Title: Role of Lignosulfonates as Superplasticizers
Author(s): M. R. Rixom and J. Waddicor
Publication: Symposium Paper
Appears on pages(s): 359-380
Keywords: admixtures; air entrainment; compressive strength;
drying shrinkage; heat of hydration; lignin and derivatives;
lignosulfonate; mechanical properties; mix proportioning; physical
properties; plasticizers; water-reducing agents; workability.
The paper describes the assessment and application of the Tattersall two point workability test and a multipoint heat of hydration apparatus in a research project to develop a super-plasticizer based on lignosulphonates. The significance of vari-ables such as ionic type, molecular weight, and degree of sulpho-nation is presented. The application of these variables to produce a suitable lignosulphonate has resulted in a superplasti-cizer which is compared with melamine and naphthalene based pro-ducts. The paper concludes that a superplasticizer based on the new lignosulphonate material is suitable for the production of flowing concrete in terms of dosage requirement, workability extension, price, and compressive strength development.