Low temperature waterproofing laminates

Disclosed are methods for waterproofing civil engineering structures using flexible, sheet-like waterproofing laminates which are applied to structures at temperatures as low as 0.degree. F. Also, disclosed are low-temperature-applicable waterproofing laminates having a bituminous layer comprising 29 to 54 weight percent asphalt, 25 to 50 weight percent process oil, and 16 to 35 weight percent thermoplastic block polymer of styrene and butadiene monomers.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to methods for waterproofing or dampproofing various 
water-penetrable construction materials in which improved, pre-formed, 
flexible sheet-like waterproofing laminates are applied to structures at 
temperatures below about 40.degree. F. Included in this invention are 
improved, pre-formed, flexible sheet-like waterproofing laminates which 
are applicable to various buildings and other civil engineering structures 
at temperatures below 40.degree. F. 
2. Description of Related Art 
Various materials used in building construction and other civil engineering 
projects such as roads, bridges, buildings, foundations, and plaza decks 
are susceptible to water penetration resulting, in part, from their 
inherent properties. Reducing or eliminating water penetration through 
structures formed of these materials often is desirable and may be 
critical in certain structures such as those housing sensitive electronic 
equipment or tunnels moving vehicular or pedestrian traffic under bodies 
of water. For many year, flexible, sheet-like waterproofing laminates of 
support films and bituminous layers pre-formed in a factory have been 
employed as waterproofing agents. 
Although pre-formed, flexible sheet-like waterproofing laminates of support 
films and bituminous layers have been used for many years, use of these 
laminates continues to be limited by the widely recognized but unmet need 
for laminates which can be applied confidently at cold temperatures. Thus, 
when ambient temperatures fall below about 40.degree. F., particularly 
below 25.degree. F., application of waterproofing laminates generally is 
abandoned and replaced by hot applied waterproofing agents. Weak lap 
adhesion, i.e., laminate to laminate adhesion at joints between laminate 
sections, is the primary factor restricting low temperature application. 
Even specialized laminates recommended for application at temperatures 
below 40.degree. F. are not applied at temperatures below 25.degree. F. 
because of weak lap adhesion. 
Flexible, pre-formed laminates of the type mentioned above and their use to 
form waterproofing layers in various kinds of building structures are 
described in, for example, U.S. Pat. Nos. 3,741,856; 3,583,682; and 
3,900,102 to Hurst. U.S. Pat. No. 4,172,830 to Rosenberg et al. is another 
of many examples disclosing sheet-like flexible materials used for 
waterproofing. 
Currently there are available waterproofing laminates recommended for 
application down to 25.degree. F. These products include a polyethylene 
layer and a bituminous layer including asphalt, process oil, rubber, and 
filler. 
U.S. Pat. No. 4,755,545 to Lalwani describes a self-sealing roofing 
adhesive blend including 50-95% by weight of a bituminous component, 4-40% 
by weight of an inert filler, and 1-6% by weight of a thermoplastic block 
polymer of styrene and butadiene monomers. 
U.S. Pat. No. 4,547,399 to Fujihara et al. discloses a composition 
effective for sealing cracks and joints in asphalt and concrete streets 
and highways that includes paving grade asphalt, process oil (not over 
32%), and styrene-butadiene rubber or rubbers. 
U.S. Pat. Nos. 4,328,147 and 4,382,989 to Chang et al. describe asphaltic 
compositions useful as roofing asphalts which include 39-99% by weight of 
oxidized asphalt and from 1-8% oxidized polyethylene. 
U.S. Pat. No. 4,459,157 to Koons describes a composition of an asphalt 
blend in which a butadiene-styrene elastomeric block copolymer is 
dispersed and contains 5-45% by weight of catalytic petroleum cracker 
bottoms oil. This composition is characterized further by a low asphaltene 
content. 
SUMMARY OF THE INVENTION 
The present invention relates to methods for waterproofing certain 
water-penetrable construction materials comprising application at 
temperatures as low as about 0.degree. F. of improved pre-formed, 
flexible, sheet-like, waterproofing laminates to structures. The improved 
pre-formed, flexible, low temperature applicable laminates used in the 
invented methods are comprised of support films and bituminous layers in 
which the bituminous component includes 29-54 weight percent asphalt, 
25-50% weight percent process oil, and 16-35 weight percent of a 
thermoplastic block polymer of styrene and butadiene monomers. 
DETAILED DESCRIPTION OF THE INVENTION 
Waterproofing of structures such as buildings, bridges, roads, tunnels, 
foundations, and plaza decks using pre-formed, flexible, sheet-like 
laminates of film and bituminous layers requires application of numerous 
sections of waterproofing laminate. To provide a continuous moisture 
barrier, the sections are overlapped and adhered together. Optimum 
waterproofing thus requires bonds between sections of waterproofing 
laminate which endure essentially for the life of the structure. The 
present invention resides in the discovery of improved waterproofing 
laminates having a bituminous layer comprised of about 29 to 54% by weight 
asphalt, about 25 to 50% by weight process oil, and about 16 to 35% by 
weight of a thermoplastic block polymer of styrene and butadiene monomers. 
As used herein, the weight percent of asphalt, process oil, and 
thermoplastic block polymer of butadiene and styrene is calculated based 
on the total of these components not including fillers or any other 
components. Further, at temperatures as low as about 0.degree. F. these 
laminates form sufficiently strong and enduring laminate-to-laminate bonds 
to enable application of the improved waterproofing laminates at these low 
temperatures. Thus, the invented low temperature-applicable waterproofing 
laminates are waterproofing laminates which form sufficiently strong and 
enduring laminate-to-laminate bonds to make possible application of 
waterproofing laminates at temperatures as low as about 0.degree. F., 
especially between 0.degree. F. and 25.degree. F., most especially between 
10.degree. F. and 20.degree. F., which meet relevant construction industry 
specifications and standards. Moreover, the invented low 
temperature-applicable waterproofing laminates retain sufficient high 
temperature flow resistance to enable application on structures where 
temperatures may exceed 140.degree. F. such as plaza decks of buildings in 
hot climates. 
As used herein, waterproofing laminates are flexible, sheet-like materials 
comprising a bituminous layer such as asphalt, rubberized asphalt, or 
equivalent materials, and a support material, preferably a film of a 
synthetic polymer such as polyethylene, polypropylene or other polyolefin; 
polyamide; polyester, e.g., polyethylene terephthalate, polyurethane, 
polyvinyl chloride; a copolymer of vinyl chloride and vinylidene chloride; 
synthetic rubber such as polychloroprene or butyl rubber; or other similar 
materials. Preferably, the bituminous layer is at least 25 mils thick, 
more preferably from 50-60 mil thick. Thus, waterproofing laminates to not 
include materials such as roofing felts wherein a bituminous material is 
impregnated into a support mat made of, for example, fiberglass, 
cellulosic materials, organic polymers, felt, or other materials to which 
asphalt will adhere. The presently invented waterproofing laminates, at 
temperatures as low as about 0.degree. F., preferably are applied to 
structures to which previously have been applied suitable primers. 
Suitable primers include known waterproofing laminate primers such as 
compositions of asphalt cutbacks, natural or synthetic rubbers and diluent 
or filler resins in organic solvents. Generally primers are not applied on 
a laminate surface which is adhered to another laminate surface at joints 
between adjacent laminate sections. 
The asphalt used in the invented, improved waterproofing laminates has the 
following alumina separation (ASTM D4124) range and preferred ranges: 
______________________________________ 
Range Preferred Range 
______________________________________ 
Saturates 5-25% 8-15% 
Naphthenic Aromatics 
20-40% 32-40% 
Polar Aromatics 30-50% 40-46% 
Asphaltenes 5-20% 8-15% 
______________________________________ 
The process oil used in the bituminous layer of the presently invented 
waterproofing laminates is operative process oil defined as a generally 
naphthenic, aliphatic, or naphthenic-aliphatic oil which has the following 
clay gel separation (ASTM D2007) range: 
______________________________________ 
Saturates 10-30% 
Polar Compounds 10-20% 
Aromatics 50-85% 
Asphaltenes 0-0.5% 
______________________________________ 
The thermoplastic block polymer of styrene and butadiene monomers is 
selected using known procedures so that the resulting bituminous layer has 
sufficient strength and tackiness to produce low temperature applicable 
waterproofing laminates. Preferred thermoplastic block polymers of styrene 
and butadiene monomers are mixtures of polymers having a butadiene:styrene 
ratio of about 70:30 and a block polystyrene content of about 30% (high 
molecular weight polymer) and polymers having a butadiene:styrene ratio of 
about 75:25 and a block polystyrene content of about 18% (low molecular 
weight polymer). More preferred are polymers in which the ratio of the low 
molecular weight polymer to the high molecular weight polymer is in the 
range of 5:1 to 1:1. Most preferred are polymers wherein the ratio of the 
low molecular weight polymer to the high molecular weight polymer is about 
4:1 to 2:1. 
Preferred waterproofing laminates of this invention include a bituminous 
layer comprising about 36 to 51 weight percent, more preferably about 39 
to 43 weight percent asphalt; about 25 to 40 weight percent, more 
preferably about 30 to 40 weight percent process oil; and about 16-35 
weight percent, more preferably about 16-25 weight percent thermoplastic 
block polymer of styrene and butadiene monomers. 
Fillers are optional ingredients in the bituminous layer of the invented 
waterproofing laminates. Useful fillers include stone dust, lime stone, 
ground glass fibers, wollastonite, sand, talc, mica, vermiculite, carbon 
black, and titanium dioxide. Addition of fillers and various other 
optional ingredients, however, may reduce the ability of the invented 
waterproofing laminates to form sufficiently strong and durable lap bonds 
at joints between sections of laminate when applied at selected 
temperatures below 40.degree. F. Thus, the types and amounts of fillers 
are selected so that the waterproofing laminate forms sufficiently strong 
and durable lap bonds when applied at temperatures as low as about 
0.degree. F. as determined by the testing procedure described below. 
A presently preferred composition for the bituminous layer of waterproofing 
laminates for low temperature application comprises about 41 weight 
percent asphalt having the above described alumina separation range, about 
38 weight percent process oil having the above described clay gel 
separation range, about 21 weight percent thermoplastic block polymer of 
styrene and butadiene monomers, and up to 5 weight percent filler. More 
preferred is this composition wherein the thermoplastic block polymer is 
an about 2:1 ratio of the low molecular weight and high molecular weight 
polymers. 
Various civil engineering structures including, for example, buildings, 
bridges, roads, tunnels, foundations, and plaza decks are made waterproof 
using the present invention. As used herein, making a structure 
"waterproof" means reducing or eliminating the ability of water to 
penetrate the structure. The presently invented waterproofing laminates 
are used to make waterproof structures constructed of materials which are 
water-penetrable either inherently or as a result if imperfections such as 
cracks or pores. The types of water-penetrable materials with which the 
present invention is used include, wood, brick, stone, exterior gypsum 
board, blended cements, pozzolanic cements, or concrete, preferably 
Portland cement concrete. 
The presently invented waterproofing laminates are prepared according to 
the following general procedure. Previously powdered or ground 
thermoplastic polymer of styrene and butadiene monomers is added to 
process oil heated to approximately 350.degree.-400.degree. F. and mixed 
until no polymer particles are apparent. Thereafter, asphalt is added to 
the polymer-oil blend with mixing until a uniform composition has formed. 
This polymer-oil-asphalt composition then is poured onto release paper and 
covered with a support film. Alternatively, the polymer-oil-asphalt 
composition is prepared by adding thermoplastic polymer to a mixture of 
process oil and asphalt heated to about 350.degree. to 400.degree. F. 
According to the presently invented methods for waterproofing structures 
wherein the invented waterproofing laminates are applied at temperatures 
as low as about 0.degree. F., preferably between 0.degree. F. and 
25.degree. F., more preferably between 10.degree. F. and 20.degree. F., 
the waterproofing laminate is applied to the structure with pressure and 
pressure is applied to form lap bonds. Preferably, pressure greater than 
hand pressure, for example, using a roller, is used. In preferred methods 
the invented waterproofing laminates are applied to vertical aspects of 
structures. In other preferred methods the waterproofing laminates are 
applied to horizontal aspects of structures. Generally, at joints between 
laminate sections the bituminous layer of one section is affixed to the 
support film of an adjacent section. Optionally, at joints the support 
film is removed from the underlying laminate section so that the 
bituminous layer of the overlying laminate section is adhered directly to 
the bituminous layer of the underlying laminate section. At joints an 
overlap width of about two inches is preferred. Primers such as mentioned 
above can be used to form lap bonds, but primerless formation of lap bonds 
is preferred. 
As used in the invented methods, application of waterproofing laminates at 
temperatures as low as about 0.degree. F., preferably between about 
0.degree. F. and 25.degree. F., more preferably between about 10.degree. 
F. and 20.degree. F., results in laminate-to-laminate bonds that are 
sufficiently strong and enduring to prevent entry of water along the 
waterproofing laminate section lap edges essentially for the life of the 
structure. 
The Example 5 test procedure was selected to predict actual use 
requirements and used to identify waterproofing laminates which when 
applied at temperatures between about 0.degree. F. and 25.degree. F. form 
laminate-to-laminate bonds of sufficient strength and duration to meet 
relevant construction industry specifications and standards. When measured 
at about 5 minutes following application at 20.degree. F., a peel force of 
2.0 pounds per linear inch approximates the minimum needed for 
waterproofing laminate-to-laminate bonds of sufficient strength and 
duration for the tested waterproofing laminate to meet relevant 
construction industry specifications and standards when applied at 
temperatures between about 0.degree. F. and 25.degree. F. Waterproofing 
laminates which meet or exceed the Example 5 criterion are referred to 
herein as low temperature-applicable waterproofing laminates. 
Contemplated equivalents of the present invention include waterproofing 
laminates having similar asphalt-polymer compositions which at 
temperatures as low as about 0.degree. F. can be applied and produce 
sufficiently strong and enduring waterproofing laminate-to-laminate bonds 
to meet construction industry waterproofing specifications and standards. 
Other contemplated equivalents are low temperature-applicable 
waterproofing laminates having a bituminous layer and a support material 
wherein some part of the bituminous layer is impregnated into the support 
material. 
The following examples provide specific illustrations of the invention, but 
are not intended to limit the scope of the invention as described above 
and claimed below.

EXAMPLE 1 
Process oil (228 g) having clay gel separation (ASTM D2007) range as stated 
above was heated to 350.degree. F. to 400.degree. F. using a heating 
mantle. Then 42 g of powdered (passes 10 mesh sieve) styrene-butadiene 
rubber having a 70:30 butadiene-styrene ratio and a block polystyrene 
content of 30% was added slowly to avoid lumping and mixed with a paddle 
mixer. Next, 84 g of ground (passes 4 mesh sieve) styrene-butadiene rubber 
having a 75:25 butadiene:styrene ratio and a block polystyrene content of 
18% slowly was added and mixed for 30 to 60 minutes. This oil and rubber 
mixture then was mixed until no rubber particles were apparent, usually 
from 30 minutes to 3 hours. Then 240 g asphalt at 300.degree. F. to 
350.degree. F. was added and mixed for 30 to 60 minutes. This rubberized 
asphalt then was poured onto release paper at a thickness of approximately 
56 mils and covered with polyethylene film. 
EXAMPLE 2 
Process oil (180 g) having clay gel separation (ASTM D-2007) range as 
stated above and asphalt (294 g) having the alumina separation (ASTM 
D4124) range stated above was heated to 350.degree. F. to 400.degree. F. 
using a heating mantle. Then 42 g of powdered (passes 10 mesh sieve) 
styrene-butadiene rubber having a 70:30 butadiene-styrene ratio and a 
block polystyrene content of 30% was added slowly to avoid lumping and 
mixed with a paddle mixer. Next 84 g of ground (passes 4 mesh sieve) 
styrene-butadiene rubber having a 75:25 butadiene-styrene ratio and a 
block polystyrene content of 18% slowly was added and mixed for 30 to 60 
minutes. This rubberized asphalt then was poured onto release paper at a 
thickness of approximately 56 mils and covered with polyethylene film. 
EXAMPLE 3 
Process oil (456 g) having the above clay gel separation (ASTM D2007) 
range, 84 g of styrene-butadiene rubber having a 70:30 butadiene-styrene 
ratio and a block polystyrene content of 30%, and 168 g of a 
styrene-butadiene rubber having a 75:25 butadiene-styrene ratio and a 
block polystyrene content of 18% was mixed at about 300.degree. to 
350.degree. F. for about one hour. Thereafter asphalt (492 g) having the 
above alumina separation (ASTM D4124) range was added and mixed for thirty 
minutes. Mixing is performed under argon gas to reduce oxidation. Then, 
the rubberized asphalt thus prepred is poured onto release paper at a 
thickness of approximately 56 mils and covered with polyethylene film. 
EXAMPLE 4 
Using the process of Example 3, a waterproofing laminate having a 
bituminous layer consisting of Process Oil (360 g) having the above 
described clay gel separation (ASTM D2007) range, high molecular weight 
polymer (84 g), low molecular weight polymer (168 g), and asphalt (588 g) 
having the above described alumina separation (ASTM D4124) range was 
prepared. 
EXAMPLE 5 
Lap Adhesion Testing 
The following procedure is used to measure bond strength of joints between 
two sections of waterproofing laminates. Waterproofing laminates with 
release paper attached was cut in sections of about 2" by 7". Using a 
scalpel 1" of the release paper is removed from one of the 2" edges of 
each section of waterproofing laminate. The area where the release paper 
was removed then is covered with masking tape to form a tab. Polyethylene 
film sections of 3" wide by 7" long also are prepared. 
For two hours prior to testing, the waterproofing laminate sections and 
polyethylene film sections are maintained at the temperature selected for 
lap adhesion testing. The release paper then is removed from the laminate 
samples and a laminate sample is affixed to a section of polyethylene 
film, and rolled three times with a 27/8" wide, twenty-pound steel roller. 
After five minutes, the laminate-film samples are placed in the mechanical 
jaws of a physical tester (Sintech.RTM.), and the physical tester 
crosshead is moved at 2" min. The force required to peel (180.degree.) 
apart the laminate and film sections then is computed and displayed as 
Peel Force in pounds per inch width of laminate. 
Testing using this procedure yielded the data in Table I, below. In the 
Table, Controls 1 and 2 are commercially available waterproofing laminates 
having a bituminous layer containing process oil, asphalt, rubber, and 
filler. Control 2 also is a commercially available product recommended for 
application down to 25.degree. F. 
TABLE I 
______________________________________ 
Peel Force (lbs/in) 
Sample 0.degree. F. 
20.degree. F. 
40.degree. F. 
73.degree. F. 
______________________________________ 
Example 1 2.2 6.1 4.2 1.4 
Example 2 &lt;1.0 5.4 5.9 3.1 
Control 1 0.0 &lt;1.0 1.2 1.6 
Control 2 0.0 &lt;1.0 2.1 2.6 
______________________________________ 
EXAMPLE 6 
High Temperature Flow Resistance 
The following procedure was used to test high temperature flow resistance 
of the invented low temperature-applicable waterproofing laminates. 
Initially, 2" wide.times.3" long.times.56 mil thick samples of the 
bituminous layer (without support film) of the waterproofing laminates was 
affixed to 20 gauge steel sheet. Then the steel sheet with bituminous 
layer affixed is conditioned horizontally at test temperature for one 
hour. Thereafter, the steel sheet is maintained vertically at testing 
temperatures for the testing duration. After the testing duration, the 
maximum sag or drippage point at the bottom of each sample is measured. 
TABLE II 
______________________________________ 
Temperature/Time (cm) 
24 Hours 48 Hours 
Sample 160.degree. F. 
180.degree. F. 
160.degree. F. 
______________________________________ 
Example 1 1.1 6.9 1.1 
Example 2 0.0 0.7 0.0 
Control 1* 
3.6 15+ 6.8 
Control 2* 
2.7 15+ 5.5 
______________________________________ 
*Controls 1 and 2 are the same as Example 5 
EXAMPLE 7 
Slow Peel Testing 
A section of galvanized steel is sprayed with a spray adhesive, and a piece 
of cross-laminated polyethylene film is placed on the adhesive. The steel 
with film attached then is allowed to dry overnight. A 56 mil thick 
section of a waterproofing laminate bituminous layer is applied to a 
backing material and cut in about 3".times.7" strips. A 1 inch wide piece 
of tape is affixed to one of the 3" wide edges. This bituminous layer test 
sample then is applied to the polyethylene film attached to the steel and 
rolled three times with a 28-pound steel roller. The steel with bituminous 
layer attached then is maintained horizontally for one hour. Thereafter, 
the sample is placed vertically with the taped tab at the top, a 100 g 
weight is attached to the tab, and the sample is maintained at 120.degree. 
F. for the testing period. Testing of the bituminous layers of Examples 3 
and 4 yielded the data in Table III: 
TABLE III 
______________________________________ 
Sample Peel Distance (cm) at 1 hr. 
______________________________________ 
Example 3 1.6 
Example 4 2.7 
______________________________________ 
The preferred embodiments of the invention are illustrated by the above. 
However, the invention is not limited to the instructions disclosed 
herein, and the right to all modifications within the scope of the 
following claims is reserved.