For My Non Muslim Students : “Do Not Disorderly In Your Affairs & Do Not Be Chaotic In Your Life”

For My Muslim Students: To avoid this, concentrate & try to understand the meaning of Al-Fatihah

POLYMER MODIFIED POLYMER MODIFIED CONCRETECONCRETE

a) Polymer Impregnated Concretea) Polymer Impregnated Concreteb) Polymer Portland Cement Concreteb) Polymer Portland Cement Concrete

INTRODUCTIONINTRODUCTION It can be divided to 2 types that is: It can be divided to 2 types that is:

a) Polymer impregnated concretea) Polymer impregnated concrete

- produced by impregnation of precast - produced by impregnation of precast hardened Portland cement concrete with a hardened Portland cement concrete with a monomer that is subsequently converted to monomer that is subsequently converted to solid polymer. solid polymer.

b) Polymer cement concreteb) Polymer cement concrete - part of the cement binder of the concrete - part of the cement binder of the concrete mix is replaced by polymer (often in latex mix is replaced by polymer (often in latex form). form).

Polymer Impregnated Concrete (PIC)Polymer Impregnated Concrete (PIC)

Made by impregnation of precast hardened Made by impregnation of precast hardened Portland cement concrete with low viscosity Portland cement concrete with low viscosity monomers (in either liquid or gaseous form) monomers (in either liquid or gaseous form) that are converted to solid polymer under the that are converted to solid polymer under the influence of physical agents (ultraviolet influence of physical agents (ultraviolet radiation or heat) or chemical agents radiation or heat) or chemical agents (catalysts).(catalysts).

Normal cured concrete has considerable Normal cured concrete has considerable capillary porosity in cement paste.capillary porosity in cement paste.

If the water present in the capillaries could be If the water present in the capillaries could be removed and replaced by a solid material, this removed and replaced by a solid material, this would greatly improve the strength and would greatly improve the strength and durability of the concrete, by eliminating much durability of the concrete, by eliminating much of this void space. of this void space.

This is the basis of polymer impregnated This is the basis of polymer impregnated concrete.concrete.

The problem of incorporating a solid into the The problem of incorporating a solid into the pore system is solved using a liquid monomer pore system is solved using a liquid monomer to impregnate the concrete and subsequently to impregnate the concrete and subsequently polymerizing the monomer to form the solid polymerizing the monomer to form the solid monomer in situ within the pores.monomer in situ within the pores.

Any types concrete regardless of the type of Any types concrete regardless of the type of cement, admixtures or aggregates used can be cement, admixtures or aggregates used can be successfully impregnated.successfully impregnated.

More porous concrete will require more More porous concrete will require more monomer and the strength of PIC is still monomer and the strength of PIC is still dependent on the final porosity of the material.dependent on the final porosity of the material.

The Making of PICThe Making of PIC

The amount of monomer needed for complete The amount of monomer needed for complete impregnation depends on the porosity of the impregnation depends on the porosity of the concrete which is determined by w/c ratio, the concrete which is determined by w/c ratio, the amount of curing, aggregate’s porosity & amount of curing, aggregate’s porosity & others.others.

The desirable properties of a monomer include The desirable properties of a monomer include low velocity, relatively high boiling point, low low velocity, relatively high boiling point, low toxicity, ease of polymerization, low cost, and toxicity, ease of polymerization, low cost, and availability.availability.

There are 3 suitable common monomers that There are 3 suitable common monomers that is:is:

a) Methyl methacrylate (MMA)a) Methyl methacrylate (MMA)

b) Monomer of plexiglassb) Monomer of plexiglass

c) Styrenec) Styrene Polyesters are too viscous to be successfully Polyesters are too viscous to be successfully

used alone, but when blended with styrene, used alone, but when blended with styrene, their viscosities can be reduced sufficiently to their viscosities can be reduced sufficiently to be used for partial impregnation of concrete.be used for partial impregnation of concrete.

Impregnation depth is limited by the Impregnation depth is limited by the followings: followings: i) the porosity of the concretei) the porosity of the concreteii)the viscosity and volatility of the monomer ii)the viscosity and volatility of the monomer and hardener and hardeneriii)the set up time of the polymeriii)the set up time of the polymeriv)the pressure appliediv)the pressure applied

PIC strength is dependent on the type and PIC strength is dependent on the type and amount of polymer used and the degree of amount of polymer used and the degree of polymerization achieved.polymerization achieved.

Production of PIC requires the following Production of PIC requires the following sequence of operations once the concrete has sequence of operations once the concrete has been cast and cured :been cast and cured :

a) Dry the concretea) Dry the concrete

b) Impregnate the concrete with monomerb) Impregnate the concrete with monomer

c) Polymerize the monomerc) Polymerize the monomer

Advantage of PICAdvantage of PIC

Remarkable improvement in tensile, Remarkable improvement in tensile, compressive and impact strength.compressive and impact strength.

Polymer impregnation strengthen the cement Polymer impregnation strengthen the cement paste and improves paste-aggregate bond.paste and improves paste-aggregate bond.

Creep of PIC is very small than plain concreteCreep of PIC is very small than plain concrete No drying shrinkageNo drying shrinkage Enhanced durability and reduced permeability Enhanced durability and reduced permeability

to water and aqueous salt solutions such as to water and aqueous salt solutions such as sulphates and chlorides.sulphates and chlorides.

ApplicationsApplications

Concrete sewer pipes, precast segments for Concrete sewer pipes, precast segments for tunnel linings, underground support systems tunnel linings, underground support systems for mining operations, railroad ties and precast for mining operations, railroad ties and precast pilings for wharves and jetties.pilings for wharves and jetties.

Applied for marine structures, wall panels, Applied for marine structures, wall panels, prefabricated, structural floors, storage tanks prefabricated, structural floors, storage tanks for seawater, desalination plants and distilled for seawater, desalination plants and distilled water plants, and high performance structure.water plants, and high performance structure.

DisadvantagesDisadvantages

The PIC are expensive. The PIC are expensive. The fabrication process of PIC is complicated.The fabrication process of PIC is complicated.

Polymer Cement ConcretePolymer Cement Concrete

Polymer Cement ConcretePolymer Cement Concrete

Made by modifying concrete or mortar with Made by modifying concrete or mortar with polymer additives (10 -15% by weight of the polymer additives (10 -15% by weight of the cement binder is replaced by polymer)cement binder is replaced by polymer)

Among the polymer additives that can be used:Among the polymer additives that can be used:a) Latexesa) Latexesb) Powdered emulsionsb) Powdered emulsionsc) Water – soluble polymersc) Water – soluble polymersd) Liquid resinsd) Liquid resinse) Monomerse) Monomers

AdvantagesAdvantages

Improve workability and reduce bleedingImprove workability and reduce bleeding Moist curing period is shorter compared to Moist curing period is shorter compared to

normal concretenormal concrete It has improved bond both to old concrete and It has improved bond both to old concrete and

to reinforcing steel.to reinforcing steel. Able to resist the entry of water and Able to resist the entry of water and

aggressive solutionsaggressive solutions Has excellent freeze-thaw, abrasion and Has excellent freeze-thaw, abrasion and

impact resistanceimpact resistance

The process technology used is very similar to The process technology used is very similar to that of conventional concrete. that of conventional concrete.

In can be cast-in-place in field applications In can be cast-in-place in field applications unlike PIC that need to be prepared as precastunlike PIC that need to be prepared as precast

Modification of concrete with a polymer latex Modification of concrete with a polymer latex (colloidal dispersion of polymer particles in (colloidal dispersion of polymer particles in water) results in greatly improved properties, water) results in greatly improved properties, at a cost.at a cost.

PCC = Cement + Polymer + Aggregates + PCC = Cement + Polymer + Aggregates + Water Water

Compressive strength of this concrete is often Compressive strength of this concrete is often higher than unmodified concrete under dry higher than unmodified concrete under dry curing condition because the strength develop curing condition because the strength develop beyond 28 days.beyond 28 days.

Drying shrinkage and creep of this concrete is Drying shrinkage and creep of this concrete is lower than unmodified concrete.lower than unmodified concrete.

Increased durability compared to plain Increased durability compared to plain concrete.concrete.

The Making of PCCThe Making of PCC

Latex Modified Concrete is one of the most Latex Modified Concrete is one of the most common type of PMC because latex is common type of PMC because latex is relatively simple to incorporate in mortar.relatively simple to incorporate in mortar.

Integration of latex improves the ductility, Integration of latex improves the ductility, durability, adhesive properties, resistance to durability, adhesive properties, resistance to chloride-ion ingress, shear bond and tensile chloride-ion ingress, shear bond and tensile and flexural strength of concrete and mortar.and flexural strength of concrete and mortar.

The sand content used in this concrete are The sand content used in this concrete are higher (about 45%) than those used in ordinary higher (about 45%) than those used in ordinary concretes (about 40%).concretes (about 40%).

ApplicationApplication

Also used extensively for patching, for floor Also used extensively for patching, for floor leveling, as a tile adhesive and to obtain skid leveling, as a tile adhesive and to obtain skid resistant surfaces.resistant surfaces.

Due to good adhesive properties, it is used for Due to good adhesive properties, it is used for laying bricks in prefabricated panels and in laying bricks in prefabricated panels and in stone and ceramic tiles.stone and ceramic tiles.

Major applications also in floors (surfacing, Major applications also in floors (surfacing, topping) and road surfacingtopping) and road surfacing

Latexes based on elastomers and epoxies are Latexes based on elastomers and epoxies are widely used for thin overlays on bridge decks widely used for thin overlays on bridge decks and parking decks to protect reinforcing steel and parking decks to protect reinforcing steel for this purpose.for this purpose.

Before and After OverlayBefore and After Overlay

Polymer Cement Polymer Cement Concrete OverlaysConcrete Overlays

Used For BridgeUsed For BridgeDeck OverlayDeck Overlay

Used For PatchingUsed For Patching