U.S. patent application number 15/303298 was filed with the patent office on 2017-02-09 for polyurethane hybrid system combining high compressive strength and early water resistance.
This patent application is currently assigned to SIKA TECHNOLOGY AG. The applicant listed for this patent is SIKA TECHNOLOGY AG. Invention is credited to Kathrin BRACHT, Lars CONRAD, Jochen GROTZINGER.
Application Number | 20170036960 15/303298 |
Document ID | / |
Family ID | 50693429 |
Filed Date | 2017-02-09 |
United States Patent
Application |
20170036960 |
Kind Code |
A1 |
CONRAD; Lars ; et
al. |
February 9, 2017 |
POLYURETHANE HYBRID SYSTEM COMBINING HIGH COMPRESSIVE STRENGTH AND
EARLY WATER RESISTANCE
Abstract
A multi-component composition including A) a polyol component
(A) including at least one polyol and water, B) a hardener
component (B) including at least one polyisocyanate, and C) a solid
component (C) including a hydraulic binder and one or more
aggregates, as an early water resistant construction or repair
material for constructing, repairing or refurbishing component
parts, wherein the mixed and applied multi-component composition is
immersed in water not later than 8 hours, preferably not later than
2 hours, after application. The use as an early water resistant
construction or repair material is especially suitable for
component parts, which are in contact with water during operation
such as offshore wind energy plants or water retaining systems,
e.g. pipelines.
Inventors: |
CONRAD; Lars; (Stuttgart,
DE) ; BRACHT; Kathrin; (Weil der Stadt, DE) ;
GROTZINGER; Jochen; (Schwabisch Gmund, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SIKA TECHNOLOGY AG |
Baar |
|
CH |
|
|
Assignee: |
SIKA TECHNOLOGY AG
Baar
CH
|
Family ID: |
50693429 |
Appl. No.: |
15/303298 |
Filed: |
April 9, 2015 |
PCT Filed: |
April 9, 2015 |
PCT NO: |
PCT/EP2015/057694 |
371 Date: |
October 11, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C04B 26/16 20130101;
C08G 18/7664 20130101; C04B 28/003 20130101; C09D 175/04 20130101;
C04B 2103/0046 20130101; C04B 28/02 20130101; C04B 2111/00543
20130101; C04B 24/02 20130101; C04B 28/02 20130101; C04B 2111/27
20130101; C04B 40/065 20130101; C04B 24/02 20130101; C04B 40/065
20130101; C04B 14/06 20130101; C04B 7/02 20130101; C04B 40/0286
20130101; C04B 40/0286 20130101; C04B 28/04 20130101; C08G 18/40
20130101; C04B 26/16 20130101; C04B 2111/74 20130101; C04B 14/06
20130101; C04B 24/282 20130101 |
International
Class: |
C04B 28/00 20060101
C04B028/00; C04B 28/04 20060101 C04B028/04 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 10, 2014 |
EP |
14164130.8 |
Claims
1. A multi-component composition comprising A) a polyol component
(A) comprising at least one polyol and water, B) a hardener
component (B) comprising at least one polyisocyanate, and C) a
solid component (C) comprising a hydraulic binder and one or more
aggregates as an early water resistant construction or repair
material for constructing, repairing or refurbishing component
parts, wherein the mixed and applied multi-component composition is
immersed in water not later than 8 hours after application.
2. A multi-component composition according to claim 1, wherein the
polyol component (A) comprises a castor oil as polyol and/or the
hardener component (B) comprises a methylene diphenyl diisocyanate
as polyisocyanate.
3. A multi-component composition according to claim 1, wherein the
component part is a component part which is in contact with water
during operation.
4. A multi-component composition according to claim 1 , wherein the
hydraulic binder comprises cement, calcined paper sludge or other
hydraulic binder system.
5. A multi-component composition according to claim 1, wherein the
construction or repair material is a flooring material, a coating
composition, a grout or a putty.
6. A multi-component composition according to claim 1, for offshore
applications, pipeline repair or lining applications.
7. A multi-component composition according to claim 1 wherein the
component part is part of a wind energy plant, a water treatment
plant, a dam, a sea wall or a water retaining system such as a
water pipeline, a sewer or a pool, or a foundation.
8. A multi-component composition according to claim 1 for
refurbishment, grouting, lock assembly or tightening of bushings or
joints.
9. A multi-component composition according to claim 1, wherein at
least part of curing of the multi-component composition is carried
out underwater.
10. A multi-component composition according to claim 1, wherein the
mixed and applied multi-component composition is immersed in water
not later than 4 hours.
11. A method for the construction, reparation or refurbishment of
component parts by means of a multi-component composition
comprising A) a polyol component (A) comprising at least one polyol
and water, B) a hardener component (B) comprising at least one
polyisocyanate, and C) a solid component (C) comprising a hydraulic
binder and one or more aggregates, wherein the method comprises the
steps of a) providing a space where the component part is to be
constructed, repaired or refurbished so that the space is not in
contact with water, b) mixing components (A), (B) and (C) of the
multi-component composition to provide a construction or repair
material, c) applying the construction or repair material on a
desired location and in a desired shape within the space provided
and initial curing of the construction or repair material to
construct, repair or refurbish the component part, and d) bringing
the component part in contact with water so that the applied
construction or repair material is immersed in water not later than
8 hours after application.
12. The method according to claim 11, wherein the application of
the construction material or repair material is by coating,
flooring, grouting or puttying.
13. The method according to claim 11, wherein at least part of
curing of the construction or repair material is carried out
underwater.
14. The method according to claim 11, wherein the mixed and applied
multi-component composition is immersed in water not later than 4
hours.
15. The method according to claim 11, wherein the applied
construction or repair material is immersed in water not earlier
than 10 minutes after application.
Description
TECHNICAL FIELD
[0001] The invention relates to the use of a multi-component
composition, which is a polyurethane hybrid system as an early
water resistant construction or repair material, and a method with
the polyurethane hybrid system for construction, repair or
refurbishment.
BACKGROUND OF THE INVENTION
[0002] Polymer-modified cements are hybrid systems comprising an
organic binder and a hydraulic binder such as cement and are known
for a long time. Polymer modification of cement mortar and concrete
can noticeably improve application and performance characteristics.
Admixtures can improve the concrete properties, e.g. in relation to
water absorption reduction, toughness enhancement, and increase of
the bond strength. Though polymers are more expensive than cement,
polymer admixtures are therefore used in particular applications
where these properties are highly valued and where the cost
performance ratio is acceptable. For instance, polymer-modified
cements are often suitable for repair applications or for
construction of floorings where particular properties are
needed.
[0003] Products based on curable starting materials such as
polyurethane cementitious hybrid systems in which the organic
binder is based on polyols and an isocyanate hardener and epoxy
cementitious hybrid systems in which the organic binder is based on
epoxy resins and an amine hardener are known. Further
polymer-modified cement systems comprise polymer latex
dispersions.
[0004] While the hydraulic binder component of such hybrid systems
can be cured under wet conditions, the organic binder component
usually requires dry conditions for cure in order to obtain a
hardened product. Thus, polymer-modified cements usually require
dry conditions until the product is fully cured.
[0005] The susceptibility of polymer-modified cements to wet
conditions during curing is a particular obstacle to their use for
the construction, repair or refurbishment of component parts, which
are in contact with water during operation, e.g. off-shore
applications. In general, construction and in particular repair is
to be carried out on site. If the construction or repair material
to be used cannot be cured underwater, specific measures such as
separating means or interruption of the operation is required. For
instance, repair applications of a water pipeline will require
interruption of operation. It is evident that it would be highly
advantageous if measures such as interruption of operation can be
reduced in time as much as possible.
[0006] AU 426554 B2 relates to a process for producing non-foaming
urethane prepolymers which comprises reacting polyisocyanate and
polyol wherein water, metal chloride and an inorganic compound such
as cement are added to the reaction system. The prepolymer can be
used for coatings on surfaces such as wet surfaces.
[0007] EP 1184364 A1 describes a particular water-soluble
polyurethane and applications thereof such as its use as a
thickening agent for underwater concrete.
SUMMARY OF THE INVENTION
[0008] The object of the present invention is to provide
construction or repair compositions which overcome the problems
discussed above and which are suitable for component parts, which
are in contact with water during operation. In particular, the
object is to provide a construction or repair material which having
a very high resistance against early water immersion and, at the
same time, exhibit high mechanical resistance, e.g. compressive
strength, and high chemical resistance after cure. A full through
cure should be possible without blisters or any other surface
failure, even at direct water contact after a short time. Moreover,
it should be possible to achieve low shrinkage during curing.
[0009] Surprisingly, this object could be achieved by using a
polyurethane hybrid system as construction or repair material for
applications under wet conditions. It was very astonishing and
against common notion that the inventors found that a polyurethane
hybrid system does not fail at a direct water contact after 30
minutes or even after 15 minutes, i.e. within an early state of the
curing period, but despite this early water contact a full through
cure was achieved and the product obtained was free of blisters or
any other surface defects and showed high mechanical resistance,
e.g. compressive strength, and high chemical resistance. These
results were very unexpected.
[0010] Accordingly, the present invention relates to the use of a
multi-component composition comprising [0011] A) a polyol component
(A) comprising at least one polyol and water, [0012] B) a hardener
component (B) comprising at least one polyisocyanate, and [0013] C)
a solid component (C) comprising a hydraulic binder and one or more
aggregates as an early water resistant construction or repair
material for constructing, repairing or refurbishing component
parts, wherein the mixed and applied multi-component composition is
immersed in water not later than 8 hours after application.
[0014] The multi-component composition used according to the
invention showed an unexpected early water resistance so that the
direct water contact within a short time after application does not
affect a full through cure resulting in outstanding mechanical
properties, such as compressive strength, and excellent surface
properties of the products obtained. Despite the water-contact
within short time after application, the surface is free of
defects, no pinholes, craters or blisters are observed. The product
obtained exhibit high water resistance and chemical resistance.
Thus, the use according to the invention is particularly suitable
for component parts, which are in contact with water during
operation.
DETAILED DESCRIPTION OF THE INVENTION
[0015] Compound names beginning with "poly" designate substances,
which formally contain, per molecule, two or more of the functional
groups occurring in their names. The compound can be a monomeric,
oligomeric or polymeric compound. For instance, a polyol is a
compound having two or more hydroxy groups, a polyisocyanate is a
compound having two or more isocyanate groups.
[0016] The average molecular weight is understood to mean the
number average molecular weight, as determined using conventional
methods, preferably by gel permeation-chromatography (GPC) using
polystyrene as standard, styrene-divinylbenzene gel with porosity
of 100 Angstrom, 1000 Angstrom and 10000 Angstrom as the column and
tetrahydrofurane as a solvent, at 35.degree. C.
[0017] The composition used according to the invention is a
multi-component composition, i.e. the composition comprises three
or more individual components. The components are stored separately
in order to avoid spontaneous reaction. The components may be
assembled together as a package. For use the components are
combined with each other. When the components are mixed together,
hydration and curing reactions begin so that the composition is to
be processed within the open time after mixing the components. The
multi-component composition preferably consists of three
components. Optionally however, one or more additional components
may be included for specific purposes. For instance, an additional
component comprising coloring agents such as pigments may be used
for coloring purposes.
[0018] Hybrid systems comprising organic binder components
including a polyol component and a polyisocyanate hardener
component suitable for cementitious applications are known to the
skilled person and commercially available, for instance products of
Sika Schweiz AG. An example for a commercially available
combination of a binder component comprising polyol and an
isocyanate hardener component are Sikafloor.RTM. PurCem products
from Sika Schweiz AG.
[0019] It is clear that the proportion of a certain ingredient in
the mixture of the components depends on the content of this
ingredient in the respective component and the mixture ratio of the
components. In the following, ratios referring to ingredients in
different components relate to suitable or correct proportions of
each component according to operating instructions, i.e. to the
mixing ratios to be used for mixing the components and, in use to
the mixture of the components prepared.
[0020] An early water resistant material refers to a material,
which can be immersed in water also if the material is not yet
fully cured, i.e. in an at least partially uncured state or in
particular in a partially uncured state. An early water resistant
material enables that at least a part of curing of the material is
carried out underwater.
[0021] In the following, the components of the multi-component
composition used according to the invention are explained at the
first.
[0022] Polyol Component (A)
[0023] The polyol component (A) comprises one or more polyols, and
water. Optionally, one or more additives may be added to component
(A). Polyol component (A) is preferably a liquid component. The
polyol component (A) may be viscous but is generally pourable.
[0024] Examples of suitable polyols are polyoxyalkylenepolyols,
also referred to as "polyetherpolyols", polyesterpolyols,
polycarbonatepolyols, poly(meth)acrylate polyols,
polyhydrocarbon-polyols, polyhydroxy-functional
acrylonitrile/butadiene copolymers and mixtures thereof, in
particular diols thereof, and mixtures thereof.
[0025] Examples of polyetherpolyols are polyoxyethylenepolyols,
polyoxypropylene-polyols and polyoxybutylenepolyols, in particular
polyoxyethylenediols, polyoxypropylenediols, polyoxybutylenediols,
polyoxyethylenetriols and polyoxypropylenetriols.
Polyoxyalkylenediols or polyoxyalkylenetriols having a degree of
unsaturation of less than 0.02 meq/g and having an average
molecular weight in the range from 1000 to 30000 g/mol and
polyoxyethylene-diols, polyoxyethylenetriols, polyoxypropylenediols
and polyoxypropylenetriols having an average molecular weight of
from 400 to 8000 g/mol are suitable.
[0026] Further examples of polyetherpolyols are so-called ethylene
oxide-terminated ("EO-endcapped", ethylene oxide-end-capped)
polyoxypropylenepolyols, styrene-acrylonitrile-grafted
polyetherpolyols, e.g. Lupranol.RTM. from BASF Polyurethanes GmbH,
Germany.
[0027] Particularly preferred polyols to be used in the present
invention are poly-hydroxy-functional fats and oils, for example
natural fats and oils, such as castor oil, or polyols obtained by
chemical modification of natural fats and oils, so-called
oleochemical polyols. Castor oil is particularly preferred.
[0028] Examples of chemically modified natural fats and oils are
polyols obtained from epoxypolyesters or epoxypolyethers obtained,
for example, by epoxidation of unsaturated oils, by subsequent ring
opening with carboxylic acids or alcohols, polyols obtained by
hydroformylation and hydrogenation of unsaturated oils, or polyols
which are obtained from natural fats and oils by degradation
processes, such as alcoholysis or ozonolysis, and subsequent
chemical linkage, for example by trans esterification or
dimerization, of the degradation products thus obtained or
derivatives thereof. Suitable degradation products of natural fats
and oils are in particular fatty acids and fatty alcohols and fatty
acid esters, in particular the methyl esters (FAME), which can be
derivatized, for example, by hydroformylation and hydrogenation to
give hydroxy-fatty acid esters.
[0029] The polyols mentioned above usually have a relatively high
molecular weight, for instance, an average molecular weight of from
250 to 30000 g/mol, in particular from 1000 to 30000 g/mol, and/or
an average OH functionality in the range from 1.6 to 3.
[0030] Further examples of suitable polyols are low molecular
weight di- or polyhydric alcohols, e.g., with a molecular weight of
less than 250 g/mol. Examples thereof are 1,2-ethanediol, 1,2- and
1,3-propanediol, neopentylglycol, diethylene glycol, triethylene
glycol, the isomeric dipropylene glycols and tripropylene glycols,
the isomeric butanediols, pentanediols, hexanediols, heptanediols,
octanediols, nonanediols, decanediols, undecanediols, 1,3- and
1,4-cyclohexanedimethanol, hydrogenated bisphenol A, dimeric fatty
alcohols, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane,
glycerol, pentaerythritol, sugar alcohols, such as xylitol,
sorbitol or mannitol, sugars, such as sucrose, other alcohols
having a higher functionality, low molecular weight alkoxylation
products of the abovementioned di- and polyhydric alcohols, and
mixtures thereof.
[0031] While said low molecular weight di- or polyhydric alcohols
may be used as the polyol, the use of the polyols mentioned above
having a high molecular weight is preferred. In a preferred
embodiment at least one high molecular weight polyol and at least
one low molecular weight di- or polyhydric alcohol are used in
combination. As mentioned, a low molecular weight polyol is
considered to have a molecular weight of less than 250 g/mol,
whereas a high molecular weight polyol is considered to have an
average molecular weight of 250 g/mol or more.
[0032] In a preferred embodiment binder component (A) comprises at
least one low molecular weight polyol, preferably in combination
with at least one high molecular weight polyol, in particular
castor oil.
[0033] Particularly preferred is a combination of one or more
polyhydroxy-functional fats and oils, such natural fats and oils,
or polyols obtained by chemical modification of natural fats and
oils, in particular castor oil, and one, two or more low molecular
weight di- or polyhydric alcohols. In such combinations, the one or
more polyols having a high molecular weight are usually used in
higher amounts than the at least one low molecular weight di- or
polyhydric alcohol.
[0034] Apart from the at least one polyol and water, the polyol
component (A) may contain further additives. Such additives are
commonly used, if desired, and typically known to the persons
skilled in the art. Examples of optional further additives are
plasticizers, pigments, adhesion promoters, such as silanes, e.g.
epoxysilanes, (meth)acrylatosilanes and alkylsilanes, stabilizers
against heat light and UV radiation, thixotropic agents, flow
improving additives, flame retardants, surface active agents such
as defoamers, wetting agents, flow control agents, deaerating
agents, biocides and emulsifiers.
[0035] Preferably used optional additives for component (A) are one
or more of plasticizers, such as benzoates, benzyl phthalates, e.g.
Santicizer.RTM.160, and diisopropylbenzene, e.g.
Benzoflex.RTM.9-88; pigments, such as inorganic and organic
pigments, e.g. Bayferrox.RTM. and Heucosin.RTM.; defoamers, such as
solvent free and silicon free defoamers, e.g. solvent free and
silicon free polymer-based defoamers, and polyorganosiloxanes, e.g.
Tego.RTM.Airex and Efka.RTM.; and emulsifiers such as calcium
hydroxide.
[0036] Hardener Component (B)
[0037] The hardener component (B) comprises one or more
polyisocyanates. Hardener component (B) is preferably a liquid
component. The hardener component (B) may be viscous but is
generally pourable.
[0038] Such polyisocyanates are commercially available and widely
used as hardener for polyols. Examples for suitable polyisocyanates
are hexamethylene diisocyanate (HDI), HDI trimers such as
Desmodur.RTM.N 3600, toluene diisocyanate (TDI), isophorone
diisocyanate (IPDI) such as Vestamat.RTM.T 1890, methylene diphenyl
diisocyanate and derivatives of these polyisocyanates, wherein HDI
and its derivatives, and methylene diphenyl diisocyanate and its
derivatives are preferred.
[0039] Monomeric and polymeric methylene diphenyl diisocyanate is
most preferred. In the following, methylene diphenyl diisocyanate
is abbreviated as MDI as usual. MDI is a useful compound, e.g. as a
starting material for polyurethane production, and produced
worldwide in millions of tons annually. A plurality of different
product grades of MDI is available. "Methylene diphenyl
diisocyanate" as this term is used in the present invention,
include, depending on its grade, monomeric and polymeric methylene
diphenyl diisocyanate.
[0040] MDI is available in the form of three different isomers,
namely 4,4'-methylene diphenyl diisocyanate (4,4'-MDI),
2,4'-methylene diphenyl diisocyanate (2,4'-MDI), and 2,2'-methylene
diphenyl diisocyanate (2,2'-MDI). Commercially available MDI can be
classified into monomeric MDI (also designated MMDI) and polymeric
MDI (PMDI) referred to as technical MDI. Polymeric MDI is the raw
product of MDI synthesis containing MDI isomers and oligomeric
species. Monomeric MDI is obtained from polymeric MDI by
purification.
[0041] Monomeric MDI refers to "pure" MDI including products of a
single MDI isomer or of isomer mixtures of two or three MDI
isomers. The isomeric ratio can vary in wide ranges. For instance,
4,4'-MDI is a colorless to yellowish solid having a melting point
of 39.5.degree. C. Commercial monomeric MDI is often a mixture of
4,4'-MDI, 2,4'-MDI and typically very low levels of 2,2'-MDI.
[0042] Polymeric MDI includes oligomeric species. Usually MDI
isomers are also included in polymeric MDI. Thus, polymeric MDI may
contain a single MDI isomer or isomer mixtures of two or three MDI
isomers, the balance being oligomeric species. Polymeric MDI tends
to have isocyanate functionalities of higher than 2. The isomeric
ratio as well as the amount of oligomeric species can vary in wide
ranges in these products. For instance, polymeric MDI may typically
contain about 30 to 80 wt. % of MDI isomers, the balance being said
oligomeric species. As in the case of monomeric MDI, the MDI
isomers are often a mixture of 4,4'-MDI, 2,4'-MDI and very low
levels of 2,2'-MDI. Polymeric MDI is typically a brown or dark
amber liquid at room temperature (23.degree. C.).
[0043] The oligomeric species are oligomers usually having a NCO
functionality of 3 or higher. The oligomeric species are a result
of the synthesis process and can be represented by the following
formula
##STR00001##
wherein n is 1 to 4 and higher. The amount of the homologues
decreases with increasing chain length. The total content of
homologues with n higher than 4 is generally not very high.
[0044] A wide variety of polymeric MDI grades is available with
varying characteristics as to the number, type and content of
isomers and oligomeric species, isomeric ratio, and weight
distribution of the oligomeric homologues. These characteristics
depend on type and conditions of synthesis and purification
procedures. Moreover, the characteristics can be adjusted, e.g., by
mixing different MDI grades according to the needs of the
customer.
[0045] The hardener component (B) comprising at least one
polyisocyanate may small amounts, e.g. up to 20 or up to 10 wt. %
of the additives all together, preferably up to 5 wt. % and more
preferably up to 2 wt. % based on the total weight of the hardener
component (B). Suitable solvents include but are not limited to
esters, ketones, hydrocarbons and chlorinated hydrocarbons. If MDI
is used, it is generally preferred however, that the hardener
component (B) comprising an isocyanate hardener essentially
consists of MDI, i.e. monomeric MDI and/or polymeric MDI, e.g. with
an amount of other additives of less than 2 wt. %. Since the MDI
products are technical products, they may, of course, include low
quantities of impurities.
[0046] Solid Component (C)
[0047] Component (C) is a solid component comprising a hydraulic
binder and one or more aggregates. Component (C) is preferably a
powder.
[0048] Hydraulic binders are widely used in construction
applications. They are usually used for concretes or mortars
typically also including aggregates and additives. For use, the
composition comprising the hydraulic binder is mixed with water so
that a reaction of the hydraulic binder and water takes place,
generally called hydration. Upon hydration, the hydraulic binder is
hardened to form a solid building material.
[0049] A hydraulic binder is a substantially inorganic or mineral
material or blend, which hardens when mixed with water. Hydraulic
binders also encompasses latent hydraulic binders or pozzolanic
binders which usually requires activation, e.g. by the presence of
lime, in order to show hydraulic properties. All hydraulic binders
known to those skilled in the art are suitable.
[0050] Typical examples of suitable hydraulic binders are at least
one of cement, e.g. Portland cement, fly ash, granulated blast
furnace slag, lime, such as limestone and quicklime, rice husk,
calcined paper sludge, fumed silica and pozzolana or a mixture
thereof. The hydraulic binder may comprise cement and/or cement
substitutes such as fly ash, granulated blast furnace slag, lime,
such as limestone, hydrated lime and quicklime, rice husk, calcined
paper sludge, fumed silica and pozzolana. Hydraulic binders such as
cement often include in addition calcium sulfate, such as gypsum,
anhydrite and hemihydrate.
[0051] The hydraulic binder preferably comprises calcined paper
sludge, a Portland cement or a mixture of Portland cement with at
least one of supplementary cementing materials such as fly ash,
granulated blast furnace slag, lime, such as limestone, hydrated
lime and quicklime, rice husk, calcined paper sludge, fumed silica
and pozzolana.
[0052] In a preferred embodiment, the hydraulic binder comprises
calcined paper sludge, a Portland cement or a mixture of Portland
cement and calcined paper sludge. In such embodiments, the
hydraulic binder may also include lime, in particular hydrated lime
(Ca(OH).sub.2) and/or quicklime (CaO), in particular when calcined
paper sludge is contained in the hydraulic binder.
[0053] By partial or complete substitution of cement, in particular
Portland cement, with one or more supplementary cementing materials
as outlined above, in particular calcined paper sludge, the
shrinkage of the composition during curing can be reduced
drastically. There is also less dust formation during addition of
component (C) when a supplementary cementing material, in
particular calcined paper sludge, is included in the hydraulic
binder.
[0054] Paper sludge is a well-known waste product of paper
production and in particular a waste product formed during deinking
of recycled paper. The latter paper sludge is also called deinked
sludge or deinked paper sludge. Paper sludge originating from the
deinking process of recycled paper is preferred.
[0055] The paper sludge is usually dried before it is calcined. The
dried paper sludge is calcined to form calcined paper sludge.
Calcination is a known process where the product is subjected to
heat treatment. The calcination conditions may vary to a large
extent depending on the composition of the paper sludge, the
desired characteristics of the product and the duration of the heat
treatment. By calcining the paper sludge the organic content is at
least partially removed and the latent pozzolanic properties of the
mineral content are activated. The calcined paper sludge is
preferably carbon-free.
[0056] The calcined paper sludge may be prepared by subjecting the
substantially dried paper sludge to temperatures e.g. in the range
of from 350 to 900.degree. C., preferably from 500 to 850.degree.
C. and more preferably from 650 to 800.degree. C. The heat
treatment may last e.g. from 1 to 8 h, preferably 2 to 5 h. The
heat treatment may be effected e.g. in a simple furnace or a
fluidized bed combustion system.
[0057] Particularly preferred calcined paper sludge is obtained
from the process described in WO 96/06057 by CDEM Minerals BV,
Netherlands, where paper sludge is calcined at a temperature in the
range of 720 to 850.degree. C. A fluidized bed system is used for
heat treatment.
[0058] Calcined paper sludge is commercially available, for
instance from CDEM Minerals BV, Netherlands, under the trade name
TopCrete.RTM.. TopCrete.RTM. is a zero carbon material.
[0059] Calcined paper sludge is usually present in form of a
powder. The color typically ranges from white to beige.
[0060] The precise composition of calcined paper sludge strongly
depends on the chemistry of the paper residue inputs and the
thermal conditions applied. Usually, the main ingredients of
calcined paper sludge are calcium compounds such as CaO,
Ca(OH).sub.2 and CaCO.sub.3, and kaolinite or preferably
metakaolinite. The calcined paper sludge may e.g. comprise,
expressed as % oxides, SiO.sub.2 (e.g. 10-40 wt. %, preferably
15-35 wt. %), CaO (e.g. 20-90 wt. %, preferably 25-60 wt. % or
30-45 wt. %), Al.sub.2O.sub.3 (e.g. 5-30 wt. %, preferably 13-20
wt. %), MgO (e.g. 1-7 wt. %, preferably 2-4 wt. %), and other metal
oxides (e.g. each less than 1 wt. %). The calcined paper sludge may
also contain volatile material, for instance in the form of
Ca(OH).sub.2 or CaCO.sub.3 or organic material the content of which
strongly depends on raw material used and the heat treatment
conditions applied.
[0061] Solid component (C) further comprises one or more
aggregates. Aggregates are chemically inert, solid particulate
materials. Aggregates come in various shapes, sizes, and materials
ranging from fine particles of sand to large, coarse rocks.
Examples of suitable aggregates are sand, such as silica sand,
gravel, and crushed stone, slag, calcined flint, lightweight
aggregates such as clay, pumice, perlite, and vermiculite. Sand, in
particular silica sand, is preferably used to reach the workability
expected and to obtain a smooth surface.
[0062] The grain size of the aggregates may vary depending on the
application, but is preferably rather small, e.g. not more than 6
mm, preferably not more than 4 mm. The aggregate may have, for
instance, a grain size in the range of 0.05 to 4 mm, wherein sand,
in particular silica sand, having a grain size in the range of 0.1
to 2 mm is particularly preferred. For instance, sand having a
grain size ranging from 0.3 to 0.8 mm or from 0.1 to 0.5 mm can be
advantageously used in the present invention. For applications such
as covering or a heavy-duty screed for trowelled finish, aggregates
such as sand having a size of e.g. 3 mm to 4 mm are suitable. The
grain size range can be determined, e.g. by sieve analysis.
[0063] Solid component (C) may optionally comprise one or more
additives, which are commonly used, if desired, and typically known
to the persons skilled in the art of cementitious applications.
Examples of suitable additives, which may be optionally used in
component (C), are superplastizicer such as polycarboxylate ether
(PCE); oil such as mineral oil, paraffin oil and organic oil,
cellulose fibers, and inorganic or organic pigments. A further
additive, which may be contained in solid component (C), is lime
such as hydrated lime, and burnt lime.
[0064] Suitable Proportions for the Multi-Component Composition
[0065] The multi-component composition of the invention is
preferably formulated such that the content of the one or more
polyisocyanates is in the range of 10 to 25% by weight, preferably
10 to 20% by weight, more preferably 15 to 20% by weight, based on
the total weight of component (A), component (B) and component
(C).
[0066] The multi-component composition is preferably formulated
such that the content of the hydraulic binder is in the range of 10
to 30% by weight, preferably in the range of 15 to 25% by weight,
based on the total weight of component (A), component (B) and
component (C). This preferred content of the hydraulic binder also
includes the weight of calcium hydroxide and/or calcium oxide, if
present. If present, the content of calcium hydroxide and/or
calcium oxide, considered alone, may be, e.g., in the range of 1 to
5% by weight, based on the total weight of component (A), component
(B) and component (C).
[0067] The multi-component composition is preferably free of metal
chloride. Free of metal chloride means that the content of metal
chloride is less than 0.05% by weight, preferably less than 0.02%
by weight based on the total weight of polyols and polyisocyanates
in the multi-component composition.
[0068] Further, the multi-component composition is preferably
formulated such that the weight ratio of water to hydraulic binder
is in the range of 0.15 to 0.35, preferably in the range of 0.2 to
0.3. The molar ratio of NCO groups to alcoholic OH groups in the
multi-component composition is preferably in the range of from 3 to
5 and more preferably in the range of from 3.5 to 4.5. Said molar
ratio further improves compressive strength of the finished
product. The molar ratio can easily be determined via the
equivalent weights of the polyols and polyisocyanates used.
[0069] Component (A) is preferably formulated such that the water
content is in the range of 10 to 40% by weight, preferably 20 to
30% by weight, and/or the content of one or more polyols,
preferably including castor oil, is 35 to 55, preferably 38 to 45%
by weight, based on the total content of component (A). In a
preferred embodiment at least one high molecular weight polyol,
preferably castor oil, and at least on low molecular polyol are
contained in component (A). In this case, the content of high
molecular weight polyol such as castor oil is e.g. in the range of
33 to 45% by weight, and the content of low molecular weight polyol
is e.g. in the range of 2 to 10% by weight, based on the total
content of component (A).
[0070] Component (C) is for instance formulated such that the
content of the hydraulic binder, including calcium hydroxide and/or
calcium oxide, if present, is in the range of 10 to 40% by weight,
preferably 20 to 35% by weight, based on the total weight of
component (C), wherein it is preferred that the hydraulic binder
comprises cement, in particular Portland cement, calcined paper
sludge or a mixture thereof. The content of one or more aggregates
is e.g. in the range of 60 to 90 wt. %, preferably in the range of
65 to 80 wt. %, based on the total weight of solid component (C).
Component (C) may also comprise one or more additives as mentioned
above.
[0071] As mentioned, in the use according to the present invention,
the hydraulic binder of component (C) preferably comprises cement,
in particular Portland cement, calcined paper sludge or a mixture
of calcined paper sludge and cement, in particular Portland cement.
If calcined paper sludge is present, the solid component (C) may
e.g. comprise from 10 to 100 wt. %, preferably from 50 to 100 wt.
%, more preferably from 80 to 100 wt. %, in particular about 100
wt. % calcined paper sludge, based on the total weight of cement,
in particular Portland cement, if present, and calcined paper
sludge in component (C).
[0072] Use of the Multi-Component Composition
[0073] When the components of the multi-component composition are
mixed, the hydraulic binder reacts with water. This reaction is
generally called hydration. Upon the reaction with the water, the
hydraulic binder is cured to a solid material. Moreover, the one or
more polyols of component (A) and the one or more polyisocyanates
of hardener component (B) react upon mixture so that the organic
binder is also cured. Thus, upon curing a hybrid solid material
comprising an inorganic binder portion and an organic binder
portion in which the aggregates are bound is formed.
[0074] The reaction of the one or more polyols and of the one or
more polyisocyanates results in cured organic binder which is a
polyurethane. Thus, the hybrid solid material after curing
comprises an inorganic network and an polyurethane network which
form the matrix of the hybrid solid material. Accordingly, the
polyurethane or polyurethane network, respectively, formed is not
soluble in water.
[0075] The multi-component composition as defined above is used as
an early water resistant construction or repair material for
constructing, repairing or refurbishing component parts, wherein
the mixed and applied multi-component composition is immersed in
water not later than 8 hours after application.
[0076] For use, the polyol component (A) and the hardener component
(B) are usually mixed with each other, and then solid component (C)
is added to this mixture. Then the mixture is applied as the
construction or repair material on a desired location and in a
desired shape to construct, repair or refurbish the component
part.
[0077] The mixed and applied multi-component composition is
immersed in water not later than 8 hours, preferably not later than
4 hours and more preferably not later than 2 hours after
application. The inventors have unexpectedly found that the mixed
and applied multi-component composition can be even immersed in
water 30 minutes or even 15 minutes after application.
[0078] A wet surface or material is not a surface or material which
is immersed in water. In particular, a surface or material immersed
in water is underwater.
[0079] Even when the mixed and applied multi-component composition
is in direct contact with water after this short time, a full
through cure is achieved and the mechanical and surface properties
as well as water resistance and chemical resistance of the cured
multi-component composition are essentially not affected by the
early water contact. Thus, the multi-component composition can be
used as an early water resistant construction or repair material.
It is, however, preferred that the mixed and applied construction
or repair material is immersed in water not earlier than 10 minutes
after application.
[0080] Accordingly, it is preferred that after application a part
of curing of the multi-component composition is carried out when
the multi-component composition is not immersed in water. At least
part of curing, preferably a part of curing, of the multi-component
composition is usually carried out when the composition is immersed
in water or underwater, respectively. Hence, in the preferred
embodiment, the applied multi-component composition is partially
cured when the multi-component composition is not immersed in
water, and the not fully cured multi-component composition is
immersed in water where curing is completed.
[0081] The curing time of the multi-component composition may e.g.
range from 15 hours to 72 hours depending on the temperature during
hardening. Thus, according to the use of the invention, the mixed
and applied multi-component composition is usually not fully cured
when it is immersed in water. Actually, it is possible to submerge
the mixed and applied multi-component composition in water when its
curing degree is rather low.
[0082] The application temperature is e.g. from about 8 to
40.degree. C., preferably from about 10 to 30.degree. C.
[0083] The water in which the mixed and applied multi-component
composition is immersed may be pure water or water comprising one
or more further ingredients, which may be dissolved and/or
dispersed in the water. Typical examples of the water for immersion
are potable water, seawater, ground water, fresh water, sewage or
wastewater.
[0084] As already mentioned, the polyol component (A) preferably
comprises a castor oil, in particular a castor oil emulsion, as
polyol. The hardener component (B) preferably comprises a methylene
diphenyl diisocyanate, in particular a polymeric methylene diphenyl
diisocyanate, as polyisocyanate. If the polyol component (A)
comprises castor oil or if the hardener component (B) comprises a
methylene diphenyl diisocyanate, in particular a polymeric
methylene diphenyl diisocyanate, the early water resistance of the
multi-component composition is improved.
[0085] As already mentioned, the hydraulic binder preferably
comprises cement, calcined paper sludge or cement and calcined
paper sludge. For this embodiment, it is also preferred that polyol
component (A) comprises a castor oil, in particular a castor oil
emulsion, and/or the hardener component (B) comprises a methylene
diphenyl diisocyanate, in particular a polymeric methylene diphenyl
diisocyanate.
[0086] The multi-component composition used as construction or
repair material is preferably a flooring material, a coating
composition, a grout or a putty.
[0087] As mentioned, the multi-component composition can be used
for construction, repair or refurbishment of component parts. It is
preferably used for repair or refurbishment of component parts.
[0088] It is preferred that the component part to be constructed,
repaired or refurbished is a component part which is in contact
with water during operation.
[0089] Suitable applications in general for the use according to
the invention are for instance offshore applications, pipeline
repair or lining applications, for instance linings of pipes and
fittings and the repair or refurbishment thereof.
[0090] The component part to be repaired or refurbished and the
substrate on which the component part is to be constructed, e.g. as
a coating, flooring or lining, may be of any material, for instance
concrete, mortar, metal, such as steel or copper, stones, bricks,
masonry, coatings, composite material or plastic.
[0091] The component part to be constructed, repaired or
refurbished may, for instance, be a part of a wind energy plant, in
particular an offshore wind energy plant, a water treatment plant,
a dam, a sea wall or a water retaining system such as a water
pipeline, a sewer or a pool, or a foundation such as a foundation
of bridges, drilling rigs or other buildings.
[0092] The multi-component composition may be used e.g. for
refurbishment, grouting, lock assembly or tightening of bushings or
joints.
[0093] Method for Construction, Repair or Refurbishment
[0094] The invention also encompasses a method for construction,
repair or refurbishment. The method for the construction,
reparation or refurbishment of component parts by means of the
multi-component composition as defined above comprises the steps of
[0095] a) providing a space where the component part is to be
constructed, repaired or refurbished so that the space is not in
contact with water, [0096] b) mixing components (A), (B) and (C) of
the multi-component composition to provide a construction or repair
material, [0097] c) applying the construction or repair material on
a desired location and in a desired shape within the space provided
and initial curing of the construction or repair material to
construct, repair or refurbish the component part, and [0098] d)
bringing the component part in contact with water so that the
applied construction or repair material is immersed in water not
later than 8 hours after application.
[0099] All above explanations with respect to the multi-component
composition and its use for constructing, repairing or refurbishing
of component parts, of course, equally apply for the method. In
particular, the applied construction or repair material is immersed
in water not later than 8 hours, preferably not later than 4 hours
and more preferably not later than 2 hours after application. It is
however preferred that the applied construction or repair material
is immersed in water not earlier than 10 minutes after application.
A contact with water means in particular immersion in water or
underwater, respectively.
[0100] The application of the construction material or repair
material can be effected by any conventional application method.
The application of the construction material or repair material is
preferably by coating, flooring, grouting or puttying.
[0101] The invention is further explained in the following
experimental part, which, however shall not be construed as
limiting the scope of the invention. The proportions and percentage
indicated are by weight, unless otherwise stated.
EXAMPLES
Example
[0102] Sikafloor.RTM.-21 N PurCem from Sika Schweiz AG was used to
produce a flooring. Sikafloor.RTM.-21 N PurCem is a three part,
water dispersed medium to high strength colored polyurethane
modified, cement and aggregate screed with self-smoothing
properties. Part A is a colored liquid, which is a waterborne
polyol, part B is a brown liquid, which is mainly methylene
diphenyl diisocyanate, and part C is a natural grey powder
comprising Portland cement, aggregate and fillers. The parts are
mixed in a weight ratio of part A/part B/part C of
3.0/3.0/15.0.
[0103] For mixing, part A is manually stirred for a short time,
then part A and part B are mixed with a low speed mixer for about 1
min. The mixture of A and B is provided in a forced action mixer
and stirred with a stirring speed of about 300 to 400 rpm while
part C is added to obtain a homogeneous mixture within about 3 min
of stirring.
[0104] The application is carried out at a temperature of
23.degree. C. The mixture obtained is poured on a concrete
substrate and spread with a trowel to obtain a floor with a
thickness of about 5 mm. The applied flooring is immersed into
water 30 minutes after application and curing is continued
underwater for a total of 24 hours.
Comparative Example
[0105] As a comparison a flooring is produced in the same way as in
the Example but the applied flooring is not immersed in water after
30 min but cured at a temperature of 23.degree. C. and 50% r.H. for
24 hours after which the product is fully cured.
[0106] Result
[0107] After 24 hours the product of the Example immersed in water
after 30 minutes is fully cured and the surface aspect is very
close to that of the product of the Comparative example not in
contact to water during curing.
* * * * *