Flame Retardant Filament for 3D Printing – What You Need To Know
There are plenty of 3d printer materials in the market, the commonly used are PLA and ABS. These materials could meet most of our needs. But in some special objects, we need to use material with unique features. Such as flame retardant and conductive.
In this article, we will talk about fire retardant material used in 3d printing.
What is fire retardant material in 3d printing?
Fire retardant is a functional material that uses for flammable polymers. It could increase the fire resistance of the material. It’s mainly used in plastic, rubber, and fiber. Especially for plastics, its application in transportation, construction, electrical equipment, aviation, space flight, etc. Fire resistance is the main problem for these parts.
As the additive of plastic, flame retardant material meets several conditions. In using flame retardant, It cannot change the physical properties of the material, such as heat resistance, mechanical strength, and electrical properties. The decomposition temperature should not be too high, but it can not be decomposed at the processing temperature. It should have good durability and weather resistance. The most important is the material compatibility, they should be uniform distribution in polymer.
Types of flame retardant mechanism
There are many types of flame retardants. According to the method of use, it can divide into two types: additive and reactive. Additive flame retardants are added to polymers by mechanical mixing method to make the polymers have flame retardancy. At present, the main additive flame retardants are organic and Inorganic halogenated flame retardants (organic chloride and organic bromide) and non-halogenated flame retardants. Organic type is some flame retardants represented by bromine, phosphorus, nitrogen, red phosphorus, and compounds, the inorganic type is mainly antimony trioxide, Magnesium hydroxide, Aluminum hydroxide, silicon flame retardant system.
Reactive flame retardants are used as monomers in polymerization so that the polymers themselves contain flame retardants, which have the advantage of having less impact on the properties of the polymers and lasting flame retardance.
Generally speaking, organic flame retardants have a good affinity. In plastics, brominated flame retardants are dominant inorganic flame retardants.
The mechanism of action of flame retardants is complex and not very clear. In general, most flame retardants are working together through several mechanisms to achieve flame retardancy.
Such as endothermic effect, covering effect, inhibition of chain reaction, non-combustion gas asphyxiation effect.
Heat Absorption Affect
At high temperatures, the flame retardant has a strongly endothermic reaction, which absorbs part of the heat from combustion, lowers the surface temperature of combustible, restrains the formation of combustible gas effectively, and prevents the spread of Combustion.
When the flame retardant is added to the combustible material, the flame retardant can form a glass-like or stable foam covering layer at high temperatures.
Inhibitory chain reaction
According to the chain reaction theory of combustion, free radicals are needed to maintain combustion. Flame retardants can act on the gas-phase combustion zone, capture free radicals in combustion reaction and prevent the flame from spreading. This can decrease flame density in the combustion zone. In the last, the combustion reaction speed will decrease to zero.
Non-Flammable asphyxiation affect
When the flame retardant is heated, it decomposes into non-combustible gas, diluting the concentration of the combustible gas to the lower combustion limit. At the same time, it also has a diluting effect on the oxygen concentration in the combustion zone, which prevents the combustion from continuing and achieves the function of flame-retarding.
Among the flame retardants, brominated flame retardants are one of the most widely used flame retardants. There’s been a lot of controversy around it. According to Investigations from scientists, it is no irritation to the skin. The acute toxicity is very low. When the original material moves into the gastrointestinal tract, it is not basically absorbed, and eventually excreted by the stool. But There’s a lot of chronic toxicity. Such as Developmental Toxicity, interference with endocrine function, Reproductive toxicity.
Flame retardants are used in transportation, electrical and electronic equipment, furniture, and building materials. When used in 3d printing, we can be used to make the case of electronic products, parts used in a high-temperature environment.
List of flame retardant filament
Generally speaking, all the fire retardant plastic could be made into 3d printing filament. Due to the temperature limit of the FDM printer, there are just three types on the list. Flame retardant PLA, Fire retardant ABS and PC/ABS filament.
Flame retardant PLA
As we have said before, PLA and abs are the most common materials in 3d printing. So does flame retardant type. Flame retardant PLA filament is a good addition to standard PLA material. It has almost the same properties as PLA. Easy for print, low shrinkage and flame retardant ability make it so interesting in printing.
Fire retardant ABS
Flame-retardant ABS plastic is opaque, generally light yellow (ivory color), but can be made by coloring any other color with a high degree of gloss products, electroplating level of the surface can be plated, vacuum coating, and other decorations. Moreover, flame retardant ABS is high in rigidity and impact strength and has excellent chemical and abrasion resistance.
Due to these properties, Fire-rated ABS can be used as a base material for making glare shields and side panel backing for airplanes.
Flame rated PC ABS
PCABS, the alloy of polycarbonate and acrylonitrile-butadiene-styrene copolymers. This material Combines the excellent properties of the two materials, the molding properties of ABS and the Mechanical Properties, impact strength, temperature resistance, and UV resistance of PC, the color is non-transparent Particles. It can Be widely used in automotive interior parts, business machinery, communications equipment, household appliances, and lighting equipment.
About flame retardant material, we recommend using flame retardant PLA and ABS. It’s easy to print and cheap. For fire-rated pc abs filament, due to the high melt temperature, Not all the 3d printers can work well with this material.
Anyway, if you know other material or ideas about 3d printing, please contact us or leave comments here.