Polymer - Carnauba wax differences
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Polymers and Carnauba wax differences
The molecular structure of all polymers are based on a chain of carbon atoms, chemically it is a molecule formed by the chemical union of five or more identical combining units called monomers. The Polymer and waxes used for detailing are semi-solid; they are actually a very concentrated solution in an organic solvent or aqueous emulsion.
Basic components
Although somewhat more complex than other products, waxes and sealants also involve just basic chemistry, when a formulator designs a wax or sealant, they consider several factors; ease of application and removal, cleaning ability (if required), depth of gloss or shine, durability and resistance to detergents / soap.
Unfortunately, no one wax or sealant product can meet all of the above characteristics. If one is emphasized and enhanced, it will be to the detriment of another. For example, increased durability means that application and removal can be more difficult. Or, if cleaning capability is emphasized, the depth of shine will be less.
The best wax or sealant to use is one that provides as many of the characteristics as possible to achieve a shiny, durable finish.
The basic components used in waxes and sealants are
- Solvents or mineral oils- used for chemical cleaning, and as a carrier system, it also makes products workable and to provide spread ability, as is the case with Carnauba wax, which in its natural state is rock hard.
- Emulsifiers - to stabilize the product (oil and water) and make it easier to use
- Very-light abrasives – Kaolin to provide mild cleaning and to aid the wax in drying consistently for easy wipe-off
- Surfactant- defined as a material that can greatly reduce the surface tension of liquids
- Coloring- purely aesthetic
- Fragrance- appealing fragrances help to sell the product
It is the combination of these ingredients that gives a wax its gloss, depth (whether paste, cream or liquid) A properly formulated wax will provide shine to a painted surface and some temporary protection. The protection is obtained by creating a buffer between the paint and the environment.
(For application differences see ‘Polish Directional Application’)
Variations
1.Polymer sealant
Comprises an open linked molecule, which forms a bond with the paint; these open linked polymer molecules join together to create an elongated mesh like effect that reflects light efficiently due to their inherent flat surface. Because they are usually very transparent they transmit the surface colour faithfully, but they have very little depth resulting in what is perceived as a very bright, flat silver glow, polymers (Zaino, Klasse, Rejex, etc) Some paint sealants contain wax; the longevity of a paint sealant is due to the type of silicone (usually amino-functional silicone) that is used in its formulation. Polymers sealants require a paint to form a convalescent (or Covalent (molecular)) bond to (usually 12-24 hours); they will not bond directly to metal to provide protection
2. Acrylic (polymer) sealants
The molecular structure of all polymers are based on a chain of carbon atoms, chemically it is a molecule formed by the chemical union of five or more identical combining units called monomers. Polyacrylate - a group of polymers which could be referred to as plastics generally, they are noted for their transparency. Some acrylate monomers (the components of the polymers) used to form acrylate polymers may be acrylic acid, butyl acrylate, 2-ethylhexyl acrylate or methyl acrylate. With polyethylene-acrylics, there is no reaction and it is more like a lacquer that dries.
These products contain polyethylene-acrylic acid that causes minor etching of the paint, which enables molecular bonding with the paint surface, which in turn results in durability versus just using a polyethylene based products. Zaino and Dura Gloss are two examples of acrylic polymers, which produce a ‘clear bright shine’. Klasse or Werkstatt (acrylic polymers) tend to produce a ‘liquid glow’. The acrylic paint solvent carrier system allows the dense molecule to spread and cross-link forming a hard protective surface. Fracture/evaporation temperatures - 265 - 285 oF (130 – 140°C)
3.Amino-Functional Silicone Fluids
Amino-Functional Silicone Fluids is a silicone fluid that has been slightly modified (the polymer content differs) the ‘amino’ portion is what causes the silicone to crosslink and physically attach to the paint surface. This cross linking capability is what makes a paint sealant more durable than a typical wax. It is the inclusion of amino-functional silicone fluids that give us a paint sealant
4.Carnauba wax (Brazil wax)
Molecules are closed linked, which means that they only butt up together to protect the surface and the wax adheres to the paint surface as opposed to bonding with the paint molecules. The wax molecules form an egg-grate type (with the long axis vertical) mesh over the smaller paint molecules of the paint film surface, which gives it an optical depth. Waxes in themselves even with the addition of silicone fluids are not as durable as the amino-functional silicones found in polymers in the formulation as they do not crosslink; but will resist many environmental contaminants only for a short period of time. Brazilian Carnauba wax is usually blended with natural oils (to provide gloss) and water-based solvents to enable it to spread and aid surface lubrication. A wax cures as opposed to cross-linking with paint surface and like most car care products Let the wax cure for 30-45 minutes before buffing, Caution; do not allow wax to entirely dry before wiping, the atmospheric conditions under which you apply the wax affect how the wax will set up and cure. Humidity affects the application because Carnauba is inherently hygroscopic (absorbs moisture) if you notice dark streaks during the application of Carnauba waxes, it tells you that the humidity is high. This will also retard the curing time.
Characteristics
Color, Depth and Clarity
The three factors concourse judges look for when scrutinizing paint film surfaces. Of the three, optical clarity is of primary importance, being able to see the paint film’s true color by having a really clean surface, clarity will enable depth of shine etc to be seen. Carnauba wax dries to a deep, natural shine; in contrast, bees wax, paraffin and many synthetic waxes tend to occlude (cloud or yellow).
Adherence
Initially, Carnauba wax attaches itself primarily by surface tension; during the curing process the carrier system (an emulsion of solvents / oils) attach themselves to the porous microscopic caps in the paint surface forming a physical anchor. Carnauba wax dries to a deep, natural shine (in contrast, bees wax, paraffin and many synthetic waxes tend to occlude (cloud)
Bonding
A Covalent (molecular) bond is formed when polymers cross-link to other molecules, resulting in a solid, durable protective layer. Carnauba wax will bond to a cross-linked (12-24 hours) polymer; conversely if a polymer is applied on top of Carnauba wax the cross-linking / bonding may be compromised. Although I would not state categorically that a product that is formulated with oils will abort the cross-linking or bonding process of a polymer; just that the process may not be as complete, and its strength and durability may be compromised. (See also Cross-linking and Adherence)
Fracture/evaporation temperatures
Polymers- 350.oF, Acrylic polymers- oF, Silicone oil 350.oF, Mineral oils 200.oF, Synthetic blends (Carnauba wax / polymers) 200.oF, Carnauba wax 180.oF, and Bee’s wax 130.oF. According to DuPont the melting point of poly (tetrafluoroethylene) PTFE is 620.°F but its properties degrade above 500. °F the downside is that it needs to be super-heated to enable it to bond
In actual practice the high temperatures frequently encountered by vehicles from the radiation causes wax compounds to melt, for example, a painted surfaces exposed to ambient temperatures of 85oF in direct sunlight, will obtain a temperature of 195 oF or more. It should be noted that there is a range of temperatures at which melting begins and that the 'melting point' is the end point of that range
Information resource
- “Automotive Detailing Inside & Out, A Knowledge Base for the Perfectionist"– by Jon Miller
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