Vinyl weatherboards first got introduced in the 1950s as a replacement for aluminium siding which was popular at that time. Vinyl is lightweight, weathers harsh weather conditions, and is low cost, low maintenance, strong and durable. Thus, it slowly started gaining popularity as exterior wall cladding. Initially vinyl weatherboards were produced by mono extrusion. Colours were subsequently mixed manually. This process produced a product that did not seem uniform and was a little low in quality.
Thus after multiple innovations, in the 1970s, the process of manufacture was modified to make a superior quality product that looked aesthetically more pleasing. Vinyl is PVC or polyvinyl chloride. These days the weatherboards are produced by a process called co-extrusion.
In this process two layers of PVC are laid out together in a continuous extrusion process. Weatherable capstock forms the top layer. This makes for one-third of the weatherboard’s thickness. This capstock has 10% titanium dioxide. This prevents the fading from UV light that normally happens in harsh sun. It does not, however, guarantee no fading. The fading happens very slowly over a period of time even in vinyl. The layer below this capstock is essentially 15% powdered limestone or calcium carbonate. This layer is called the substrate. This is used to balance out the titanium dioxide so that both the layers extrude uniformly at the same rate and maintain the same level of fluidity. This ensures that the vinyl weatherboards stay uniform. Some small amounts of mercaptan or butadiene is also added as a stabilizer. This helps take care of any hydrochloric acid that may be released with passing time in the weatherboard. Some other additives like lubricants are added to smoothen the manufacturing process.
This is the basic composition of vinyl weatherboards. Of course, as the thicknesses and grades in vinyl sideboards vary, the quality varies too. Certain other additives may be added as well to get the final product of a specific type. The better grades and prices of vinyl offer more protection from fading or denting as well as better aesthetics. It must be kept in mind though that darker colours tend to fade faster than lighter palettes. Some products also apply a UV coating to the surface of the weatherboard to help prevent fading and other damage from harsh sunlight.
Vinyl weatherboards also come pre-fabricated with their own fastening or locking systems that will be later fastened to the exterior wall of the home. This is done during extrusion. This is the composition of vinyl weatherboards as well as a peek into its manufacturing process.
Article from: http://www.vinylcladdingprofessionals.com.au