The advanges of HPMC & MHEC in dry mix mortar products
November 22nd 2024Control joints are essentially deliberate cracks cut into concrete floors that allow for movement caused by temperature and moisture changes. Put another way, when the concrete does inevitably shrink and crack, it does so on a line (at the bottom of the control joint) instead of randomly across the slab. If left unfilled, control joints can become areas for dirt, debris, and moisture to collect and cause problems.
Filling joints with a non-compressible, hard material supports the edges of the joint from stresses imposed by heavy, hard-wheeled traffic. Joint filling should be put off as long as possible to allow the joint to widen, although in practice joints are usually sealed or filled sooner than ideal.
Selecting a joint filler can be challenging; not only are there several brands to choose from, but the joint fillers themselves are available with different chemical compositions and physical properties. The two most common joint filler types are epoxy and polyurea.
Hydroxypropyl methylcellulose (HPMC) is a non-ionic cellulose prepared from natural polymer materials through a series of chemical processing.
It is suitable for building dry powder mortar, internal and external wall putty powder (paste), adhesives, joint filler, joint cover, interface agents, coatings, and self-leveling agents for new building materials.
Concrete joint sealants and joint fillers differ in terms of chemical formulation and intended use. Elastomeric joint sealants are cold-applied, elastomeric one- or multi-component materials for sealing, caulking or glazing operations on buildings, squares and decks used by vehicles or pedestrians, and for other types of construction than road and airport pavements and bridges. The main purpose of joint sealants is to prevent water, dirt and debris from entering the joints. Designed to be able to expand and contract with the joint, sealants are relatively soft and pliable materials, usually polyurethane, silicone or acrylic.
Hard wheeled vehicles, trolleys and pallet handlers running over sealant filled joints can cause them to deflect, leaving the joint edges unprotected. This leads to edge cracking and spalling. The best use for joint sealants in industrial flooring is therefore to fill joints that are not affected by traffic, such as isolation joints at walls or columns and under racks.
Industrial floor joints subject to heavy and/or hard wheel traffic should be filled with semi-rigid joint fillers. These are polyurea or epoxy resin materials.
Semi-rigid joint fillers restore the continuity of concrete floors that have been disrupted by cutting joints into the surface. Because they are hard and relatively inflexible, joint fillers protect the edges of joints from damage caused by wheel impact and heavy loads. Filling these joints allows the wheels to roll over the joint as if it were a continuous concrete surface, while still allowing the joint to continue to perform its job of relieving stresses within the slab.
What are the characteristics of epoxy adhesives and joint fillers?
The epoxy adhesives and joint fillers used are adhesives with high chemical resistance and resistance to various elements. The application of epoxy adhesives and joint fillers is very important. In order to create a durable floor suitable for long-term use, the application instructions should be followed.
In addition, a skilled person must inspect the floor before applying epoxy adhesive caulk; it must be free of any dirt, grime and cracks. You should ensure that there is a smooth floor underneath before application. It is also important to ensure that your clean floor is completely dry. The durability of the surface to be applied will be at its highest level if it is clean and smooth.
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