PVC Resins are classified by their K-Value, an indicator of the molecular weight and degree of polymerization.
• K70-75 are high K value resins which gives best mechanical properties but are more difficult to process. They need more plasticizer for same softness. High performance Cable insulations in Suspension resin and tough coatings for Conveyor belts, Industrial Flooring and similar high end applications in Paste grade are some popular application. It is the costliest.
• K65-68 are medium K value resin which are the most popular. They have a good balance of Mechanical properties and processibility. UPVC (Unplasticised or Rigid PVC) is made from the less porous grades while Plasticised Applications are best made from the more porous grades. There is a lot of grade choice as they cater to the Majority of PVC applications. Because of its sheer volume this family of PVC resins are priced the lowest.
• K58-60 are low K-value ranges. Mechanical properties are lowest, but processing is easiest. Many difficult to process applications like injection moulding, blow moulding and Clear Calendered packaging film are made from the lower K value ranges. Prices are higher than Medium K Value Resins.
• K50-55 are special resins which are tailor made for some demanding applications. Interesting ones are Battery Separator Resins and Blending resins used along withPaste Grade resin to reduce costs. Processing is easiest.
As PVC is 56% Chlorine, it is one of the few Polymers which are self extinguishing, as Chlorine is a strong Flame inhibitor.
What is the K value in PVC?
K – Value is a measure of degree of polymerization or number of monomers in PVC chain or molecular weight. Since the % of PVC in films and sheets is predominant, its K value plays a very important role. K – Value has effect on properties of PVC resin, processing as well as properties of product. 7.
What is k67 PVC resin?
PVC Resin Virgin (K -67), commonly abbreviated PVC, is the third-most widely produced polymer, after polyethylene and polypropylene. The rigid form of PVC is used in construction for pipe and in profile applications such as doors and windows.
What is PVC resin?
Poly Vinyl Chloride Resin or PVC Resin as it is popularly called, is a thermoplastic Resin which can be softened on reheating. A common term for this commodity polymer is Vinyl. Often available in the form of a powder, PVC granules are highly resistant to oxidisation and degradation caused by atmospheric reaction.
What is K value?
K-value is simply shorthand for thermal conductivity. Thermal conductivity, n: the time rate of steady state heat flow through a unit area of a homogeneous material induced by a unit temperature gradient in a direction perpendicular to that unit area.
How do you calculate the k value?
They can be calculated as 1 / (the sum of the resistances of the various layers of the element (its R-values) + the resistance of the internal and external surfaces of the element).
Are there different grades of PVC?
There are two common types of PVC pipe – schedule 40 PVC and schedule 80 PVC. Schedule 40 PVC is usually white in color and schedule 80 is usually a dark gray (they can also be found in other colors). Their most important difference, though, is in their design. Schedule 80 pipe is designed with a thicker wall.
What is UPVC used for?
UPVC, also known as Unplasticized Polyvinyl Chloride, is a low-maintenance building material used as a substitute for painted wood, mostly for window frames and sills when installing double glazing in new buildings, or to replace older single glazed windows.
How do you calculate k value?
To calculate the K-Value of insulation, simply divide the thickness (in inches) by the R-Value.
What is a K value?
K-value is simply shorthand for thermal conductivity. Thermal conductivity, n: the time rate of steady state heat flow through a unit area of a homogeneous material induced by a unit temperature gradient in a direction perpendicular to that unit area. This definition is really not that complex.
What is K in viscosity?
K value (viscosity), is an empirical parameter closely related to intrinsic viscosity, often defined in slightly different ways in different industries to express viscosity based estimate of statistical molecular mass of polymeric material used particularly for PVC.
What is the chemical formula for PVC?
PVC is Polyvinyl Chloride . This is a plastic that has the following chemical formula: CH2=CHCl (see picture on the right). Plastic covers a wide rage of synthetic or semi-synthetic polymerization products (i.e. long-chain carbon-based “organic” molecules) which name refers to the fact that in their semi-liquid…
What is the chemical reaction of PVC?
PVC is made using a process called addition polymerization. This reaction opens the double bonds in the vinyl chloride monomer (VCM) allowing neighboring molecules to join together creating long chain molecules. nC2H3Cl = (C2H3Cl)n vinyl chloride monomer = polyvinylchloride
What are the physical properties of PVC?
Physical and mechanical properties: PVC is an atactic polymer and therefore essentially uncrystallized. However, it sometimes happens that, locally, over short chain segments, PVC is syndiotactic and can assume the crystalline phase, but the percent shear fracture never exceeds 10 to 15 %. The density of PVC is 1.38 g/cm3.
Post time: Apr-07-2022