All of Rhino’s plastic mud guards are rated to UV8. This means the Rhino Guards material can withstand at least 8000 hours of sunlight. In addition, the colouring used in Rhino Guards has the highest possible rating for resistance to colour fading.
Why do mudguards fade?
We are constantly being approached by customers who are tired of dealing with plastic guards that fade. Below we draw on the expertise of our partners and go in-depth to explain what this actually means. We finish by posing some questions about why colour fading is occurring in other mud guards.
Photo below: Popular competitor mudguard in Australia on a truck with one faded guard (left) and one new guard not yet faded (right). Notice the huge difference in colour between faded and unfaded.
Photo below: Trailer with Rhino Guards (9 years old); the colour has minimal fading.
Most of this article is written by Steve Lewis, the General Manager of Vision Plastics who have been a trusted supplier of Rhino for a number of decades. Steve has experience in manufacturing both polyethylene plastic and colour pigments. Steve explains…
Polyethylene is used in the production of a large range of products. These products range from single use plastics that we all hear so much about in the media, through to infrastructure components that have a 20-to-30-year life expectancy in full exposure to the elements. Plastic water tanks are a good example of a long-life polyethylene product.
Polyethylene as a base material has limited resistance to UV exposure. Most polyethylene parts are also coloured with a pigment. I am sure that everyone has seen plastic parts that have suffered from excessive colour fading and at times visible degradation of the material which can result in material failures.
Many factors affect the life expectancy of polyethylene parts. These range from initial material selection, part design, pigment selection and the UV package selected in the part design. Manufacturing method also influences the longevity of a part. Rhino mud guards are Rotationally Moulded using high grade LLDPE specifically designed for the rotational moulding process. This material is supplied from the polymer manufacturer with a high quality UV and anti-oxidant package included into the base polymer. The polymer used in Rhino mud guards has been tested by exposing the material to high levels of UV at a similar wavelength as the sun. This test is also conducted at an increased temperature and humidity level to increase the demand on the UV protection. This test exposes the samples for at least 8000 hours before they are tested to ensure that sufficient physical properties of the material remain. This material is then given the rating UV8. There is no direct calculation to state how long a plastic part that has been tested to UV8 will last in service. However, the standard UV protection for plastic water tanks is UV8 so it would be reasonable to expect these parts to last for a number of years before UV degradation results in failure.
Colour is then added by compounding pigments into the base polymer. These pigments have high heat stability and excellent light fastness. Pigment light fastness is measured on the Blue Wool Scale. This scale has ratings from 1 to 8; 1 being low resistance to fading and 8 being high resistance to fading. Pigments used in the rotational moulding process have a high rating, usually 8 which is the highest rating on this scale. This means that significant colour change and fading is not expected over the life of the mudguard.
Thanks for your input Steve. Will, our GM finishes the article below by summarising.
In summary
We don’t know why other plastic mudguards fade. It could be manufacturers:
- compromising quality by removing saving on the cost of UV stablisers. The cost can often be in excess of 10% of the material cost.
- Including a UV stabliser but one that is rated low, i.e. not UV8.
- If a UV Stabliser is included, not using the required add rates or controlling dose rates.
- Using inferior colour pigments that are low on the Blue Wool Scale.
If your current plastic guards are fading, we would suggest asking all of the following questions:
- What are the products rated to?
- Is a UV stabliser added?
- What are the add rates are for UV stabilisers? What are the controls to ensure the add rate is consistent?
- What are the colour pigments?
If you can’t get a straight answer then it is probably time to switch to a Rhino Guard!