GASCONTROL PLAST - PE pressure pipes, plastic boardsy

Plastic boards

Extrusion of polypropylene board 1 – 50 mm thick is intended as construction material for welding of basins, cartages and containers, see table of Assortment »

Polypropylene and polyethylene are consisted of saturated hydrocarbon chain, and that is why is classified as polymer with high chemical resistance against regular (20 °C) and increased temperature (60 °C). They resist the influence of water, inorganic alkalis, salts and acids, if they don’t have oxidation effect. They don’t dissolve in organic resolvent at normal temperatures. Strong oxidation reagents such as nitric acid, oleum and halogens attack them. In general can be said, that against oxidation is PP less resistant than PE. In aliphatic hydrocarbons and some oils they swell at increased temperatures, while their characteristics are changing at the same time. PP are much more corrosion resistant at tension than PE.

Products are approved for use in Czech Republic and they are in accordance with standard CSN EN 15 013 and CSN EN 14 632, see Atest »

Influence of chemical

Water

PE and PP have very small absorption in water.

Inorganic salts

Inorganic salts don’t react with PP and PE neither in solid state or aqueous solution if they don’t have oxidation action. Inorganic salts with oxidation action activate oxidation of PP and PE already at normal temperature. At PE some inorganic salts activate corrosion at tension.

Inorganic acids

PP and PE is stable against those inorganic acids, which don’t have oxidation action. Oxidation acids, especially nitric acid, cause fast corrosion. Halogen acids provoke at PE and PP corrosion at tension.

Inorganic alkali

Alkali metal hydroxides neither in solid state nor in solutions don’t react both with PP and PE and doesn’t occur their diffusion. Mechanical properties of polymers don’t change even after long time operation.

Halogens

Halogens react with both PP and PE. Causes halogenation of polymer chains and their splitting. At the same time the mechanical properties are rapidly decreasing. Halogens are for contact with PP and PE absolutely inapplicable.

Organic
acids

Organic acids don’t react both with PP and PE but some of them diffuse and partly change their mechanical properties. In general the speed of diffusion grows with increasing temperature and concentration of acid. Some of the organic acids activate at PE corrosion at tension.

Alcohols

Alcohols don’t react with PP and PE. Some alcohols can diffuse in polymers mostly without major changes of mechanical properties. At PP the alcohols with longer aliphatic chains or aromatic can cause swelling at higher temperature. At PE some alcohols activate corrosion at tension.

Ester

At normal temperature the esters don’t usually erode PP. At higher temperature can occur swelling of PP, which is connected with changes of mechanical properties. Esters get through the polyethylene and activate corrosion at tension. Esters are not recommended for long time contact with PE.

Aliphatic hydrocarbon

Aliphatic hydrocarbons, both saturated and unsaturated, easily diffuse PP and PE already at normal temperature and they cause swelling and change of mechanical properties of polymer. Aliphatic hydrocarbons also cause at both PP and PE corrosion at tension.

Aromatic hydrocarbon

Aromatic hydrocarbons act similar with PP and PE as aliphatic, they also cause corrosion at tension. Aromatic hydrocarbons melt the PP and PE at higher temperature.

Halogen-hydrocarbon

Most of the aliphatic and aromatic halogenhydrocarbons diffuse the PP and PE and activate swelling, change of mechanical properties and corrosion at tension. Resistance depends on temperature.