How does cross-linking affect mechanical properties?
Mechanical Analysis In all cases, crosslinking significantly increased Young’s modulus and UTS, and reduced strain at failure (Table 2). High-strain modulus also tended to increase significantly after genipin and disulfide crosslinking when performed under fixed volume conditions.
What is cross-linked polyethylene used for?
Cross-linked polyethylene, commonly abbreviated PEX, XPE or XLPE, is a form of polyethylene with cross-links. It is used predominantly in building services pipework systems, hydronic radiant heating and cooling systems, domestic water piping, and insulation for high tension (high voltage) electrical cables.
How is polyethylene cross-linked?
Cross-linked polyethylene (XLPE) is a thermosetting resin with three types of cross-linking: peroxide cross-linking, radiation cross-linking, and silane cross-linking. The polymer can be effectively recycled if only the cross-linking points are decomposed.
How is cross-linked polyethylene different from regular polyethylene?
Cross-linked polyethylene is high-density polyethylene that is manufactured by adding a catalyst to the thermoplastic resin, which turns it into a thermoset. The result is a plastic that possesses impact resistance, tensile strength and resistance to fracture that linear polyethylene can’t match.
How does cross-linking affect polymer properties?
When polymer chains are crosslinked, the material becomes more rigid. In polymer chemistry, when a synthetic polymer is said to be “cross-linked”, it usually means that the entire bulk of the polymer has been exposed to the cross-linking method. Low cross-link densities increase the viscosities of polymer melts.
Why does cross-linking improve the strength of polymers?
7.24 Explain how cross linking improves the strength of polymers. o Crossed linked polymers contain additional bonds between the molecules that provide resistance to flow. All of the extra links or bonds must be broken before the molecules can move relative to each other. Some polymers are conductive naturally.
What are cross links in polymers?
In chemistry and biology a cross-link is a bond or a short sequence of bonds that links one polymer chain to another. These links may take the form of covalent bonds or ionic bonds and the polymers can be either synthetic polymers or natural polymers (such as proteins).
What is cross linked polyolefin?
Cross linked polyolefin (XLPO) is a broad category of organic materials. Polymer is produced from a simple olefinic monomer that reacts with fellow chain members to form polymeric chains. Monomers are reactive single chain molecules. This polymer chain becomes it’s own new material.
What is highly cross linked polyethylene?
Background: Highly cross-linked polyethylene (XLPE) was developed to address the problem of wear and osteolysis associated with metal-on-conventional ultra-high molecular weight polyethylene (UHMWPE) bearing surfaces.
How does cross-linking improve the strength of polymers?
By cross-linking, the structure of a polymer solution can be fixed. The resulting polymer networks (or gels) show elastic behavior and, depending on the system, good mechanical properties. Polymer networks are able to swell by uptaking water or organic solvents.
What is the function of cross-linking?
– Cross linking is used to refer the process of linking one site to another site and provide a way to allow the accessing to it. – It doesn’t need to be owned by the same person as it provides the methods that have been be built on the Internet.
What is properties of cross-linked polymers?
Cross-linked polymers have many interesting properties which make them very attractive materials. By cross-linking, the structure of a polymer solution can be fixed. The resulting polymer networks (or gels) show elastic behavior and, depending on the system, good mechanical properties.
What does cross-linked polyethylene mean?
Cross-linked polyethylene, commonly abbreviated PEX or XLPE, is a form of polyethylene with cross-links. It is formed into tubing, and is used predominantly in building services pipework systems, hydronic radiant heating and cooling systems, domestic water piping, and insulation for high tension electrical cables.
What is cross – link polyethylene?
XLPE cable (cross-linked polyethylene) is hydronic tubing that is manufactured from polyethylene plastic with a three-dimensional molecular bond that is created within the structure of the plastic.
What is cross-linked polyethylene insulated cable?
Crosslinked polyethylene insulated sheathed cable is a single core or multi-core wire with insulating sheathed layer suitable for power distribution networks or fixed laying in industrial installations with rated power frequency voltage up to and including 0.6/1kv.
What is cross – linked polymer?
When polymer chains are crosslinked, the material becomes more rigid. In polymer chemistry, when a synthetic polymer is said to be “cross-linked”, it usually means that the entire bulk of the polymer has been exposed to the cross-linking method. The resulting modification of mechanical properties depends strongly on the cross-link density.