Glossary of Terms
ABS Acrylonitrile butadiene styrene copolymer
Acetal Also known as POM polyoxymethylene or polyformaldehyde
Acrylic See PMMA
Additive A substance added to a masterbatch to provide a function other than colouration. Additives can aid processing or give final product functionality
Agglomerate A small cluster of undispersed pigment
Anti-oxidant An additive which prevents oxidation
Anti-Static An additive which dissipates any static electricity build-up
Ash test A gravimetric analysis of masterbatch or compound whereby the polymer is burned off and remaining inorganic ash is measured or analysed
Biopolymer Polymers produced by living organisms or derived from biomatter, e.g. cellulose, starch, proteins, PLA (Poly lactic acid).
Biodegradable Able to chemically breakdown in a physiological environment
Carbon Black Black pigment
Carrier system The polymer and additive(s) combination upon which a masterbatch is based
Colourant An additive which imparts colour
Commodity Polymer Non engineering polymer used for commodity applications e.g. packaging usually Polyolefins
Colour match PMB procedure for development of new colour formulations
Copolymer Polymer consisting of two or more monomer units
Crystallisation The ordered structuring of molecules within the bulk of a substance
De-nester Additive to improve separation of plastic articles particularly trays
Dispersion The even spreading of pigment into a masterbatch
Distribution The even spreading of masterbatch into a plastic article/product
Dyestuff A polymer soluble colourant
Engineering Polymers Polymers primarily used for engineering and technical mouldings, generally with superior physical properties to commodity polymers e.g. ABS, Nylon, PBT
EVA Ethylene vinyl acetate
Extrusion Process used by PMB for making masterbatch, mixture is melted, compounded and forced though a die by two co-rotating screws, strands formed which are cooled and pelletised.
Filler An additive used instead of polymer, reduces RMC and improves processability
Fluorescent A type of pigment/dyestuff capable of absorbing visible and non-visible wavelengths and releasing them quickly as light energy of a desired wavelength producing characteristic bright colours
Formulation A recipe for a masterbatch containing the amounts of each polymer, additive and pigment/dyestuff per kg
GPPS General purpose polystyrene
HDPE High density polyethylene
Heat stability Temperature at which a substance will thermally degrade causing loss of colour or functionality
Heat test Test performed using an injection moulder to ascertain the Heat stability by incrementally increasing the temperature
HIPS High Impact Polystyrene
Homopolymer Polymer consisting of one monomer unit only
Iridescent A type of pearlescent pigment which appears a different hue depending on the angle of view
Inorganic Not based on carbon compounds, usually mineral derived
Injection moulding Process of heating and forming plastic articles, performed at PMB as part of QC and colour matching
LDPE Low density polyethylene
Let down rate (LDR) Percentage of masterbatch to be used relative to total polymer weight
Light fastness Ability of a substance to withstand degradation due to visible light, measure with the blue wool scale from 1(low)-8(high)
Luminescent Refers to a type of pigment which absorbs visible and non-visible wavelengths and releases them slowly over a period of time as visible light, glow in the dark
Masterbatch A preparation of pigments, dyestuffs and/or additives with a polymer base
Metallic Pigment based on metal, usually aluminium or bronze, which imparts a metallic sheen
MFI Melt flow index, a measure of the viscosity of a polymer where the higher the number the easier the flow
Mica The base mineral from which most pearlescent pigments are made, can be made synthetically
Monomer The single repeating unit within a polymer chain
Nib See Pellet
Nucleating agent Additive which causes nucleation
Nucleation Physical process whereby crystallisation is assisted by "seeding" with another additive
Nylon See PA
Opaque Does not allow any light transmission
Organic Containing carbon, usually oil derived
Oxo-degradable Able to chemically degrade when exposed to air
PA Polyamide (Nylon) available in many varieties e.g. PA6, PA66, PA12
PBT Polybutylene terephthalate
PC Polycarbonate
Pearlescent A type of pigment which imparts a pearl-type lustre
Pellet Single granule of masterbatch or polymer
PET Polyethylene terephthalate
Photodegradable Able to chemically degrade when exposed to visible and non-visible radiation
Pigment Non polymer soluble colourant, organic and inorganic
PMMA Poly methyl methacrylate (Acrylic)
Polymer Substance consisting of long chain like molecules based on carbon
Polyolefin Polymer containing only carbon and hydrogen
PP Polypropylene
PVC Polyvinylchloride
Slip An additive which reduces the surface co-efficient of friction enabling two surfaces to slip over one another
Shrinkage Moulding effect whereby the resultant moulding will be slightly smaller than the mould cavity, caused by crystallisation of the polymer.
Thermochromic An additive which changes colour when subject to temperature variations
Thermoplastic A substance which can be melted and re-melted any number of times
Thermoset A substance which when heated and set cannot be re-melted due to cross linking of polymer chains
Titanium dioxide White pigment
TPE Thermoplastic elastomer
Translucent Allows light transmission but imparts haze
Transparent Allows light transmission with no haze
UV Pack Additive system which protect polymers and container contents against UV radiation
Weather resistance Ability of a substance to withstand the effects of the weather, measured on the Grey scale 1-5 where the higher the number the better the resistance
Warpage A distortion effect caused by crystallisation of the polymer
Wax A low molecular weight additive that melts before the polymer and wets out the pigments enabling them to be dispersed within the polymer matrix.
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