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α-Allyl-ω-methoxypolyethylene glycol-maleic anhydride copolymers were synthesized with side chain lengths n EO from 0-130 and characterized by aqueous GPC. A representation of their molecular conformation (e.g. worm-, brush-or star-like polymers) was developed. The amount of polymer adsorbed on cement rapidly decreases with increasing side chain length n EO. Zeta potential measurements using the electroacoustic method in cement paste with w/c = 0.5 indicate that worm-like copolymers with n EO ≤ 7 adsorb flat ("train" type) and form a densely packed, thin polymer film. In this case, the adsorbed amount of copolymer is high. For star polymers with n EO ≥ 34, preferred orientation of the polymer main chain is perpendicular to the cement surface ("tail" type). The result is a thick polymer layer, with a second electrochemical double layer on top. For star polymers, the adsorbed amount is low because of the higher surface occupancy of horizontally layered side groups.

Micro- and nanomaterials can i) reduce cement consumption in concrete, ii) improve durability of cement-based constructions and iii) modulate particle release.

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