Chemical resistance refers to durability against chemicals. Chemical-resistant piping is required in facilities where chemicals are often handled, for example in chemical plants and semiconductor factories. Chemicals include acids, alkalis and organic solvents, and if these come into contact with materials with low chemical resistance, corrosion and expansion can occur, leading to chemical leakage in the pipework in the worst case. The chemical resistance of CPVC is presented here.

High chemical resistance

Many commonly used piping materials have low chemical resistance or, if they do have chemical resistance, it is biased towards acids, alkalis or organic solvents. As there are only a limited number of piping materials that exhibit high overall resistance, facility designers need to check the properties of each content they are handling and select the appropriate piping.
One of the strengths of CPVC is its overall high resistance to acids and alkalis. For example, when compared to the chemical resistance of Fe (iron), PC (prestressed concrete), PA (polyamide) and PP (polypropylene), which are commonly used as piping materials, CPVC has a higher chemical resistance than other materials in many types of acids and alkalis.

Benefits of high chemical resistance

The inside of pipes through which chemicals flow are gradually eroded by acids, alkalis and other substances. This occurs not only with strong acids and alkalis, but also with weak acids and alkalis, leading to age-related deterioration. As a result, the flow in the pipework is obstructed and excessive pressure is generated in the pipework, which can lead to damage.
The high chemical resistance of CPVC reduces the rate of erosion, which has the advantage of extending the durability of the pipework and reducing running costs. In addition, large-scale pipework maintenance in chemical plants and semiconductor plants requires the production line to be temporarily shut down, which has a significant impact on plant productivity. In other words, for the plant side, the adoption of chemical-resistant piping is an important topic that affects not only running costs but also plant productivity.

SEKISUI CHEMICAL Group’s CPVC compound “Durastream” has a product line-up that can be used for a wide range of chemical applications. Furthermore, the raw materials are designed based on chemical resistance evaluations that utilise our knowledge as a pipe manufacturer, so they are highly regarded by many customers as high-quality, stable CPVC compounds.