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Joints in Concrete Structures
Published in Suchintya Kumar Sur, A Practical Guide to Construction of Hydropower Facilities, 2019
Sealant is a material that is applied to fill and protect the joint that exists between the two surfaces. It is used to seal the gap so that water cannot permeate and corrode the concrete and embedded steel. It also increases the bond between the surfaces.
Polymers: Types, properties and applications
Published in Marios Soutsos, Peter Domone, Construction Materials, 2017
Sealants are elastomeric materials, which can be used for sealing joints against wind and water in construction. Thin curtain wall construction employs highly effective materials to provide the heat installation, but generally there is no cavity for the dispersion of water that may leak through the joints on the outside. In addition, in the event of air blowing directly to the inside of a joint, there must be an effective material to provide heat insulation; consequently, a baffling system to provide this must be installed. Therefore, adhesive and elastic sealants are required to enable this type of construction to be used efficiently.
Inductive loop installation and loop system sensitivity
Published in Lawrence A. Klein, ITS Sensors and Architectures for Traffic Management and Connected Vehicles, 2017
Sealant may be applied with a special applicator or by hand directly from a container. A paint stirrer can be inserted into the slot to hold the wire down while the sealant is being applied. Other techniques can also be used (e.g., backer rod strips and nylon rope) to hold the wire securely in place as sealant is added. The sealant application procedure is completed by removing any excess material from the pavement and dusting talc or sand on the fresh sealant before opening the lane to traffic. This prevents tracking of the sealant during its curing process and allows earlier opening of the traffic lane.
A Novel High-strength Autologous Fibrin Glue Augmented with Biocompatible Polymers
Published in The Journal of Adhesion, 2023
Anindya Karmaker, Mahmudul Hasan, Shafayet Ali, Kazi Md Asif, Shoeb Ahmed
The formation of a fibrin clot is the body’s natural way to halt the bleeding and speed up the healing process. This natural healing mechanism has motivated the creation and development of several types of bioadhesives. The three most frequent forms of bioadhesives utilized in surgical applications are hemostatic agents, tissue adhesives, and sealants.[4] Even though the three adhesive kinds have distinct names, they work similarly and are classified based on the application stage and purpose. Hemostatic drugs improve primary hemostasis, induce fibrin production and prevent fibrinolysis.[5] In the event of a surgery, a major injury, or bleeding management, hemostatic agents, or simply hemostats, may be required to control blood loss.[6] Because of their viscose and paste-like flowable matrix, some commercially available hemostats may be injected directly into the wound region,[4].[7] Tissue adhesives are a class of natural and synthetic substances that are currently employed in a variety of local applications for hemostasis, wound closure, and fistula healing. The most often used tissue adhesives include cyanoacrylates, fibrin glues, and thrombin.[8] Through polymerization or crosslinking reaction, tissue adhesives form an insoluble matrix in the wound.[9] A sealant is a substance that is used to prevent fluids from passing through a surface, joints, or gaps in materials.[4] Most tissue adhesives and hemostats can act as sealants.
Efficacy of Ozone Pretreatment on Fissure Sealant Adaptation and Retention
Published in Ozone: Science & Engineering, 2022
Tugba Bezgin, Firdevs Tulga Oz, Nurhan Ozalp
Although there are numerous options for sealant materials, resin-based sealants are the main preferred type (Botton et al. 2016; Kuhnisch et al. 2020). The preventive effect of resin PFSs depends on their retention ability in the absence of microleakage, resulting in better clinical success (Ahovuo-Saloranta et al. 2017; Kuhnisch et al. 2020). However, the retention of resin PFSs with only acid etching pretreatment is questionable. In-vivo studies revealed considerably low retention rates when conventional acid-etched sealants were applied (Bhushan and Goswami 2017; Erbas Unverdi, Atac, and Cehreli 2017). Furthermore, several in vitro studies have shown some microleakage when sealants were applied with conventional method (Cehreli et al. 2010; Duangthip and Lussi 2003; Pardi et al. 2006). Remaining pellicle and debris which could not be removed from the base of the fissure by prophylaxis and acid etching prior to sealant placement may be the reason for the failure of PFSs (Celiberti, Pazera, and Lussi 2006; Dukic, Dukic, and Milardovic 2009; Garcia-Godoy and De Araujo 1994).
Aging mechanism of hot-poured sealants for asphalt pavement under natural environmental exposure
Published in International Journal of Pavement Engineering, 2022
Liping Cao, Chen Yang, Zejiao Dong, Weijun Wang, Huiming Yin
Sealants are also directly exposed to complex natural environmental conditions, such as sunlight, rain, and radiation, which induce serious aging problems and lead to premature failure. The field investigation (Figure 1) shows that the early natural aging of sealant is characterised by the formation of 3–5 mm depth fine net cracks accompanied with surface hardening and decrease of adhesion on the surface. The bottom sealant remains intact and consistently exhibits good road performance. The net cracks on the surface of the sealant will gradually heal with the increase of atmospheric temperature in the later stage. However, the material properties will be irreparably damaged after the sealant surface is hardened. These fine cracks may not affect the normal service capacity of the sealant in a short time. Nevertheless, the surface layer of the sealant will be fragile during the later service and can easily peel off under vehicle load due to the gradual deepening of surface aging. The next layer of the sealant after peeling will be exposed to the natural environment and will continue aging and peeling until it loses its watertight function, thereby accelerating pavement damage. Therefore, natural aging is one of the main reasons for net cracks on the sealant surface and has a direct impact on its road performance.