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Their addition allows to decrease the water-to-cement ratio of concrete or mortar without negatively affecting the workability of the mixture. It enables the production of self-consolidating concrete and high-performance concrete. The water–cement ratio is the main factor determining the concrete strength and its durability. Superplasticizers ...
The phenolic units are mainly linked by methylene and/or ether groups. The molecular weights are in the low thousands, corresponding to about 10–20 phenol units. Obtained polymer is thermoplastic and require a curing agent or hardener to form a thermoset. Hexamethylenetetramine is a hardener added to crosslink novolac. At a temperature ...
ε c (t) = is strain of filled polymer ε m (t) = is strain of matrix or unfilled polymer E m = is Young's Modulus of matrix E c =is the Young's Modulus of filled polymer. The better the filler bonds with the matrix the better creep resistance will be. Many interactions will have a positive influence.
Polymer concrete is a type of concrete that uses a polymer to replace lime-type cements as a binder. One specific type is epoxy granite , where the polymer used is exclusively epoxy . In some cases the polymer is used in addition to portland cement to form Polymer Cement Concrete (PCC) or Polymer Modified Concrete (PMC). [ 1 ]
The degree of polymerization, or DP, is the number of monomeric units in a macromolecule or polymer or oligomer molecule. [1] [2] [3]For a homopolymer, there is only one type of monomeric unit and the number-average degree of polymerization is given by ¯ ¯ = ¯, where ¯ is the number-average molecular weight and is the molecular weight of the monomer unit.
A lower ratio leads to higher strength and durability, but may make the mix more difficult to work with and form. Workability can be resolved with the use of plasticizers or super-plasticizers. A higher ratio gives a too fluid concrete mix resulting in a too porous hardened concrete of poor quality.
Advanced diamond-like carbon (DLC) coated polymer composites have been reported [39] where the coating increases the surface hydrophobicity, hardness and wear resistance. Ferromagnetic composites, including those with a polymer matrix consisting, for example, of nanocrystalline filler of Fe-based powders and polymers matrix.
Polymer concrete is concrete which uses polymers to bind the aggregate. Polymer concrete can gain a lot of strength in a short amount of time. For example, a polymer mix may reach 5000 psi in only four hours. Polymer concrete is generally more expensive than conventional concretes. [citation needed]