Monday, December 04, 2023
Friday, November 25, 2022
Earth Shield® TPV (thermoplastic vulcanizate) (aka TPE-R) Waterstop is the world's leading chemical-resistant waterstop, with renowned physical properties and broad-spectrum resistance to hazmat, deleterious fluids, and concentrated ozone. NSF 61 certified and GreenSpec listed. Earth Shield® Thermoplastic Vulcanizate Waterstop (TPV) (aka TPE-R), by J P Specialties, dramatically expands the scope of conventional waterstop by offering unmatched chemical resistance to a broad spectrum of aggressive chemicals, solvents, and hot petroleum oils. EPA-compliant waterstop profiles are available for new construction and retrofit, and the necessary tools and accessories for proper installation.
Wednesday, April 20, 2022
Waterstop Tortuous Fluid Flow Path
You can quantify the effectiveness of a waterstop by calculating its fluid flow path. The fluid flow path is measured from the waterstop hydraulic side to the dry side. Ribbed waterstop profiles are much more effective than the traditional dumbbell varieties. The series of fins (or ribs) substantially exaggerates the fluid flow path from the hydraulic side to the dry side compared to the older standard dumbbell profiles (see the illustration below).
Friday, September 24, 2021
Understanding the difference between TPER and TPV is the key to writing more robust specifications for chemical-resistant waterstop. The key is in the crosslinking of the rubber phase. Polymers are chemical compounds formed by multiple structural units called monomers.
In the laboratory, forming polymers from monomers is called polymerization and is often so complex that it has to be initiated or sustained by heat, pressure, or a catalyst. Synthetic polymers produce plastics, synthetic fibers, and synthetic rubber.
Polymers come in different forms and have certain qualities (strength, elasticity, resistance to solvents, and temperature extremes), achieved through vulcanization, where individual polymer molecules form crosslinks.
The vulcanization of polymers leads to springy rubber molecules that can become locked together to a greater or lesser extent. These molecules form rubber or elastomers. The end material is stronger, much more durable, and more resistant to chemicals.
Elastomers are amorphous polymers, the result of crosslinking rubber molecules through vulcanization.
An elastomer can exist in two states:
• Uncured elastomers are a gelatinous mass with the consistency of chewing gum in its natural state.
• Cured elastomers (i.e., vulcanized elastomers) are rubber-like materials that can be stretched to twice their original length. Thanks to their crosslinks, they return to most of their original length when released.
Plastic or thermoplastic polymers consist of long polymer molecules that are not linked to each other, i.e.; they have no crosslinks. They can generally go through many melt/freeze cycles without suffering chemical change.
Thermoplastics include polyethylene, polypropylene, polystyrene, polyester, polyvinyl chloride, acrylics, nylons, and polyurethanes.
Fundamental differences exist between thermoplastic polymers and thermoset rubber. Thermoset rubber generally demonstrates a better elastic behavior and a better memory than a thermoplastic material. They are also better suited to high-temperature applications. Thermoset rubber is not easily recyclable like thermoplastic, which can be melted and reshaped.
Thermoset rubber refers to a range of elastomers that vulcanize to a more robust form through the addition of energy (heat or irradiation). The added power and catalysts cause the molecular chains to link into a rigid, 3D structure. However, once vulcanized, they cannot be melted and reshaped.
Important thermosets include phenolics, urea, melamine, epoxies, polyesters, silicones, rubbers, and polyurethanes.
THERMOPLASTIC ELASTOMERS (TPER)
Thermoplastic elastomers (TPERs) are a diverse family of rubber-like compound materials that combine the functional performance and properties of conventional thermoset rubbers with the processability of plastics. TPERs permit the fabrication of rubber-like products with the ability to be reshaped or reformed with the application of heat.
THERMOPLASTIC VULCANIZATES (TPV)
Thermoplastic vulcanizates (TPVs) belong to the thermoplastic elastomer (TPER) family. TPVs are chemically crosslinked rubber within a thermoplastic polymer phase.
The level of vulcanization (partial versus full) has an impact on the properties of the TPV. A fully vulcanized TPV demonstrates improved performance than a partially or non-vulcanized one (thermoplastic polyolefin or TPO).
TPVs have outstanding properties, including excellent elastic recovery, high-temperature resistance, and chemical resistance.
A TPV molecule — Crosslinked rubber phase encased in a thermoplastic matrix.
Saturday, May 22, 2021
Waterstops for Environmental Compliance of Liquid Tight Concrete Structures is a targeted course of instruction and professional development for engineering firms engaged in the design of chemical, industrial, and environmental projects such as secondary containment of hazardous waste, industrial wastewater, ozone contactors, and others. The course is technical in nature and describes waterstops role in fluid-proofing concrete joints, chemical resistant polymers and steels, and state and federal regulations of compliance.
Thursday, April 22, 2021
Saturday, April 17, 2021
J P Specialties, Inc. is pleased to showcase the above photograph, which illustrates a successful waterstop repair with our custom "V-Iron" waterstop splicing tool. The V-Iron provides the waterstop installer with an efficient means to repair and replace damaged, forgotten, or misplaced waterstop cast-in-situ concrete. The product has male and female points at 45°, which allows for a miter cut transition, maintaining ribs and centerbulb continuity.
We manufacture a complete line of waterstop installation and repair tools. Click here to learn more.
Friday, March 19, 2021
Modern water treatment facilities, particularly ozone contactor structures, have utilized Earth Shield® waterstop for over 20 years. Earth Shield® thermoplastic vulcanizate (TPV) waterstop is immune to the corrosive effects of concentrated ozone. Our TPV polymer waterstop is suitable for ozone exposures up to 600 pphm (parts per hundred million).
Tuesday, March 16, 2021
Lead is a metal used in the plumbing and waterworks industry. Lead can dissolve into the water supply from drinking water system components it contacts (pipes, fittings, waterstops, et al.). The maximum lead content in drinking water system components is 0.25%, as defined by the NSF 372 Standard.