View source for Additive (adhesives, paints, and plastic)

== Description ==

In terms of polymers or paints, an additive is a chemical substance, usually in small quantities, that is added to a base material for the purpose of modifying the properties of the end product. Additives an change the performance (flexibility, UV resistance, etc.) or appearance ( color, opacity, etc.). Plastics and paints often contain around 20 additives, most of which are unlisted components considered trade secrets. As such, their toxicity to humans and the environment is often unknown.  Some of the additives are weakly bound to the polymeric matrix which can lead to separation and/or degradation.

Examples of additives include: 
{| class="wikitable" 
|-
! Additive Type
! Typical concentration (%)
! Description
! Example compounds
! Comments
|-
| [[accelerator]]
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| [[Adhesion promoter]]
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| tackifier
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| [[antioxidant]]
| 0.5-3.0
| Protects against degradation, especially during processing
| Also called stabilizer. Phenols, phosphite esters, some thioethers
| Almost all plastics with  contains some type of stabilizers.
|-
| Antisag agent 
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| Antiskin agent
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| [[Antistatic agent]]
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| [[Biocide]]
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| also called antimicrobial
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| Blowing agent
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| Clarifying agent
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| [[Coalescing agent]]
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| [[Colorant]]
| 0.001- 10
| Used to give color or opacity
| Any [[dye]] or [[pigment]]
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| [[Defoaming agent]]
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| [[Dispersant]]
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| [[Drier]]
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| [[Emulsifier]]
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| [[Filler]]
| 0-50
| Also called bulking agents. they change the mechanical and optical properties, while producing a less expensive product
| [[Talc]], [[chalk]], [[glass bead]], [[glass fiber]], [[carbon black]], [[carbon fiber]]
| Most polymers contain fillers.  High level protect against UV rays
|-
| [[Flame retardant]]
| 1-30
| Used to minimize burning
| Most commonly used are brominated and chlorinated paraffins
| Non-chlorinated organophosphates are safer but do not work as well
|-
| Heat stabilizer
| 0.3-5
| Minimizes degradation due to heat exposure
| Formerly derivatives of lead, tin and cadmium were used. Alternatives are barium/zinc mixtures  and calcium stearates
| Primarily used in PVC
|-
| [[inhibitor]]
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| Impact modifier
| 10-40
| Improved toughness and resistance to damage
| Usually an elastomeric copolymer such as butadiene, styrene, etc.
| Chlorinated polyethylene is used for PVC
|-
| Light stabilizer
| 0.05-3
| Protects against UV damage
| HALS, UV blockers and quenchers
| Normally only used in products designed for outdoor use
|-
| [[Lubricant]]
| 0.1-3
| Used to assist in the process of forming/molding plastic; also called [[Release agent|release agents]] and slip agents
| PFASs (hazardous), [[paraffin wax]], wax ester, metal stearates ([[zinc stearate]], etc.), fatty acid amides (oleamide, erucamide, etc.)
|
|-
| [[plasticizer]]
| 10-70
| Provide flexibility
| [[Phthalate ester|Phthalates]] are most common followed by adipate ester and citrate esters
| PVCs use the most plasticizers followed by cellulose acetate.  Phthalates leach out with time and are considered carcinogenic
|-
| [[size]]
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| [[thickening%20agent|Thickener]]
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|}

== Synonyms and Related Terms ==

additives (pl.); modifier; admixture; Additive (Deut.); additif (Fr.); aditivo (Port.)

==Resources and Citations==
* Monona Rossol, 'Water-Based Latex Paints'
* Theodore J. Reinhart, 'Glossary of Terms', '2019 NYCOSH webinar on paints handout, Engineered Plastics'', ASM International, 1988
* ASTM, "Standard Terminology Relating to Paint, Varnish, Lacquer and Related Products", Annual Book of ASTM Standards, Section 6, Paints, Related Coatings and Aromatics, ASTM, D16, 7-Jan, Jul-96
* Matt Roberts, Don Etherington, ''Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology'', U.S. Government Printing Office, Washington DC, 1982
* Art and Architecture Thesaurus Online, http://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000
* Wikipedia: http://en.wikipedia.org/wiki/Additive (Accessed Feb. 2, 2006)
* Wikipedia: [https://en.wikipedia.org/wiki/Plastic#Additives |Plastic Additives] (Accessed June 2023)



[[Category:Materials database]]