polymer chemistry Polymer chemistry is a sub-discipline of chemistry that focuses on the structures of chemicals, chemical synthesis, and chemical and physical properties of polymers and macromolecules. The principles and methods used within polymer chemistry are ...

solid Solid is one of the State of matter#Four fundamental states, four fundamental states of matter (the others being liquid, gas, and Plasma (physics), plasma). The molecules in a solid are closely packed together and contain the least amount o ...

viscous The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity quantifies the inter ...

polymer A polymer (; Greek '' poly-'', "many" + ''-mer'', "part") is a substance or material consisting of very large molecules called macromolecules, composed of many repeating subunits. Due to their broad spectrum of properties, both synthetic a ...

organic compound In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The ...

phenolic compounds In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of one or more hydroxyl groups (— O H) bonded directly to an aromatic hydrocarbon group. The simplest is phenol, . Phenolic compounds are c ...

parasitoid In evolutionary ecology, a parasitoid is an organism that lives in close association with its host (biology), host at the host's expense, eventually resulting in the death of the host. Parasitoidism is one of six major evolutionarily stable str ...

sesquiterpene Sesquiterpenes are a class of terpenes that consist of three isoprene units and often have the molecular formula C15H24. Like monoterpenes, sesquiterpenes may be cyclic or contain rings, including many unique combinations. Biochemical modificatio ...

longifolene Longifolene is the common (or trivial) chemical name of a naturally occurring, oily liquid hydrocarbon found primarily in the high-boiling fraction of certain pine resins. The name is derived from that of a pine species from which the compound wa ...

delta-cadinene Cadinenes are a group of isomeric hydrocarbons that occur in a wide variety of essential oil-producing plants. The name is derived from that of the Cade juniper (''Juniperus oxycedrus'' L.), the wood of which yields an oil from which cadinene ...

resin acid Resin acid refers to mixtures of several related carboxylic acids, primarily abietic acid, found in tree resins. Nearly all resin acids have the same basic skeleton: three fused rings having the empirical formula C19H29COOH. Resin acids are tacky, ...

amber Amber is fossilized tree resin that has been appreciated for its color and natural beauty since Neolithic times. Much valued from antiquity to the present as a gemstone, amber is made into a variety of decorative objects."Amber" (2004). In Ma ...

Balm of Gilead Balm of Gilead was a rare perfume used medicinally, that was mentioned in the Hebrew Bible, and named for the region of Gilead, where it was produced. The expression stems from William Tyndale's language in the King James Bible of 1611, and has c ...

Dipterocarpaceae Dipterocarpaceae is a family of 16 genera and about 695 known species of mainly tropical lowland rainforest trees. The family name, from the type genus ''Dipterocarpus'', is derived from Greek (''di'' = two, ''pteron'' = wing and ''karpos'' = fru ...

dragon's blood Dragon's blood is a bright red resin which is obtained from different species of a number of distinct plant genera: ''Calamus'' spp. (previously ''Daemonorops'') also including ''Calamus rotang'', '' Croton'', '' Dracaena'' and ''Pterocarpus''. ...

elemi ''Canarium luzonicum'', commonly known as elemi, is a tree native to the Philippines. The oleoresin harvested from it is also known as elemi. Synonyms * ''Canarium carapifolium'' G.Perkins * ''Canarium oliganthum'' Merr. * ''Canarium polyanthu ...

frankincense Frankincense (also known as olibanum) is an aromatic resin used in incense and perfumes, obtained from trees of the genus ''Boswellia'' in the family Burseraceae. The word is from Old French ('high-quality incense'). There are several species o ...

Ferula gummosa ''Ferula gummosa'' is a perennial herb of ''Ferula'' in the family Apiaceae. It is native to Iran and Turkmenistan. Its gum resin is called galbanum Galbanum is an aromatic gum resin and a product of certain umbelliferous Persian plant specie ...

Guaiacum ''Guaiacum'' (''OED'' 2nd edition, 1989.Entry "guaiacum"
in
kauri gum from trees of '' Agathis australis'',

hashish Hashish ( ar, حشيش, ()), also known as hash, "dry herb, hay" is a drug made by compressing and processing parts of the cannabis plant, typically focusing on flowering buds (female flowers) containing the most trichomes. European Monitorin ...

(Cannabis resin) from '' Cannabis indica'', labdanum from mediterranean species of ''

Cistus ''Cistus'' (from the Greek ''kistos'') is a genus of flowering plants in the rockrose family Cistaceae, containing about 20 species (Ellul ''et al.'' 2002). They are perennial shrubs found on dry or rocky soils throughout the Mediterranean region ...

'',

mastic (plant resin) Mastic ( el, Μαστίχα) is a resin obtained from the mastic tree (''Pistacia lentiscus''). It is also known as tears of Chios, being traditionally produced on the island Chios, and, like other natural resins, is produced in "tears" or dropl ...

from the mastic tree ''

Pistacia lentiscus ''Pistacia lentiscus'' (also lentisk or mastic) is a dioecious evergreen shrub or small tree of the genus ''Pistacia'' native to the Mediterranean Basin. It grows up to tall and is cultivated for its aromatic resin, mainly on the Greek islan ...

'',

myrrh Myrrh (; from Semitic, but see '' § Etymology'') is a gum-resin extracted from a number of small, thorny tree species of the genus ''Commiphora''. Myrrh resin has been used throughout history as a perfume, incense and medicine. Myrrh mi ...

from shrubs of '' Commiphora'',

sandarac Sandarac (or sandarach) is a resin obtained from the small cypress-like tree ''Tetraclinis articulata''. The tree is native to the northwest of Africa with a notable presence in the Southern Morocco part of the Atlas mountains. The resin exudes n ...

resin from ''

Tetraclinis articulata ''Tetraclinis'' (also called arar, araar or Sictus tree) is a genus of evergreen coniferous trees in the cypress family Cupressaceae, containing only one species, ''Tetraclinis articulata'', also known as Thuja articulata,styrax (a

Benzoin resin Benzoin or benjamin (corrupted pronunciation) is a balsamic resin obtained from the bark of several species of trees in the genus ''Styrax''. It is used in perfumes and some kinds of incense and as a flavoring and medicine (see tincture of benz ...

from various '' Styrax'' species) and spinifex resin from Australian grasses.

Amber Amber is fossilized tree resin that has been appreciated for its color and natural beauty since Neolithic times. Much valued from antiquity to the present as a gemstone, amber is made into a variety of decorative objects."Amber" (2004). In Ma ...

is

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

resin (also called resinite) from coniferous and other tree species. Copal, kauri gum, dammar and other resins may also be found as subfossil deposits. Subfossil copal can be distinguished from genuine fossil amber because it becomes tacky when a drop of a solvent such as

acetone Acetone (2-propanone or dimethyl ketone), is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile and flammable liquid with a characteristic pungent odour. Acetone is miscib ...

or

chloroform Chloroform, or trichloromethane, is an organic compound with chemical formula, formula Carbon, CHydrogen, HChlorine, Cl3 and a common organic solvent. It is a colorless, strong-smelling, dense liquid produced on a large scale as a precursor to ...

is placed on it. African copal and the kauri gum of New Zealand are also procured in a semi-fossil condition.

Rosin

Rosin is a solidified resin from which the volatile

terpene Terpenes () are a class of natural products consisting of compounds with the formula (C5H8)n for n > 1. Comprising more than 30,000 compounds, these unsaturated hydrocarbons are produced predominantly by plants, particularly conifers. Terpenes ar ...

s have been removed by distillation. Typical rosin is a transparent or translucent mass, with a vitreous fracture and a faintly yellow or brown colour, non-odorous or having only a slight turpentine odour and taste. Rosin is insoluble in water, mostly soluble in alcohol,

essential oil An essential oil is a concentrated hydrophobic liquid containing volatile (easily evaporated at normal temperatures) chemical compounds from plants. Essential oils are also known as volatile oils, ethereal oils, aetheroleum, or simply as the o ...

s,

ether In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again be c ...

, and hot fatty oils. Rosin softens and melts when heated and burns with a bright but smoky flame. Rosin consists of a complex mixture of different substances including organic acids named the

resin acid Resin acid refers to mixtures of several related carboxylic acids, primarily abietic acid, found in tree resins. Nearly all resin acids have the same basic skeleton: three fused rings having the empirical formula C19H29COOH. Resin acids are tacky, ...

s. Related to the terpenes, resin acid is

oxidized Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a d ...

terpenes. Resin acids dissolve in

alkali In chemistry, an alkali (; from ar, القلوي, al-qaly, lit=ashes of the saltwort) is a basic, ionic salt of an alkali metal or an alkaline earth metal. An alkali can also be defined as a base that dissolves in water. A solution of a ...

s to form resin soaps, from which the resin acids are regenerated upon treatment with acids. Examples of resin acids are

abietic acid Abietic acid (also known as ''abietinic acid'' or ''sylvic acid'') is an organic compound that occurs widely in trees. It is the primary component of resin acid, is the primary irritant in pine wood and resin, isolated from rosin (via isomerizat ...

(sylvic acid), C₂₀H₃₀O₂,

plicatic acid Plicatic acid is a carboxylic acid from the resin acid group. It is naturally found in '' Thuja'' and cypress resin. It is the main irritant and contact allergen present in thuja wood. (''Cf.'' pine, where the primary irritant is abietic acid.) T ...

contained in cedar, and pimaric acid, C₂₀H₃₀O₂, a constituent of galipot resin. Abietic acid can also be extracted from rosin by means of hot alcohol. Pimaric acid closely resembles abietic acid into which it passes when distilled in a vacuum; it has been supposed to consist of three isomers. Rosin is obtained from

pine A pine is any conifer tree or shrub in the genus ''Pinus'' () of the family Pinaceae. ''Pinus'' is the sole genus in the subfamily Pinoideae. The World Flora Online created by the Royal Botanic Gardens, Kew and Missouri Botanical Garden accep ...

s and some other

plant Plants are predominantly photosynthetic eukaryotes of the kingdom Plantae. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi; however, all current definitions of Plantae exclud ...

s, mostly

conifers Conifers are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All extan ...

. Plant resins are generally produced as stem secretions, but in some Central and South American species of ''

Dalechampia ''Dalechampia'' is a genus of plant of the family Euphorbiaceae and of the monogeneric subtribe Dalechampiinae. It is widespread across lowland tropical areas (generally below 2,000 m ASL) primarily in the Americas with smaller numbers of species ...

'' and '' Clusia'' they are produced as pollination rewards, and used by some stingless bee species in nest construction. Propolis, consisting largely of resins collected from plants such as

poplars ''Populus'' is a genus of 25–30 species of deciduous flowering plants in the family Salicaceae, native to most of the Northern Hemisphere. English names variously applied to different species include poplar (), aspen, and cottonwood. The we ...

and

conifer Conifers are a group of conifer cone, cone-bearing Spermatophyte, seed plants, a subset of gymnosperms. Scientifically, they make up the phylum, division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single ...

s, is used by honey bees to seal small gaps in their hives, while larger gaps are filled with beeswax.

Petroleum- and insect-derived resins

Shellac is an example of an insect-derived resin. Asphaltite and Utah resin are petroleum

bitumen Asphalt, also known as bitumen (, ), is a sticky, black, highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product, and is classed as a pitch. Before the 20th century, the term a ...

s.

History and etymology

Human use of plant resins has a very long history that was documented in

ancient Greece Ancient Greece ( el, Ἑλλάς, Hellás) was a northeastern Mediterranean civilization, existing from the Greek Dark Ages of the 12th–9th centuries BC to the end of classical antiquity ( AD 600), that comprised a loose collection of cult ...

by

Theophrastus Theophrastus (; grc-gre, Θεόφραστος ; c. 371c. 287 BC), a Greek philosopher and the successor to Aristotle in the Peripatetic school. He was a native of Eresos in Lesbos.Gavin Hardy and Laurence Totelin, ''Ancient Botany'', Routledge ...

, in ancient Rome by

Pliny the Elder Gaius Plinius Secundus (AD 23/2479), called Pliny the Elder (), was a Roman author, naturalist and natural philosopher, and naval and army commander of the early Roman Empire, and a friend of the emperor Vespasian. He wrote the encyclopedic '' ...

, and especially in the resins known as

frankincense Frankincense (also known as olibanum) is an aromatic resin used in incense and perfumes, obtained from trees of the genus ''Boswellia'' in the family Burseraceae. The word is from Old French ('high-quality incense'). There are several species o ...

and

myrrh Myrrh (; from Semitic, but see '' § Etymology'') is a gum-resin extracted from a number of small, thorny tree species of the genus ''Commiphora''. Myrrh resin has been used throughout history as a perfume, incense and medicine. Myrrh mi ...

, prized in ancient Egypt. These were highly prized substances, and required as

incense Incense is aromatic biotic material that releases fragrant smoke when burnt. The term is used for either the material or the aroma. Incense is used for aesthetic reasons, religious worship, aromatherapy, meditation, and ceremony. It may also be ...

in some religious rites. The word ''resin'' comes from French ''resine'', from Latin ''resina'' "resin", which either derives from or is a

cognate In historical linguistics, cognates or lexical cognates are sets of words in different languages that have been inherited in direct descent from an etymology, etymological ancestor in a proto-language, common parent language. Because language c ...

of the Greek ''rhētínē'' "resin of the pine", of unknown earlier origin, though probably non-

Indo-European The Indo-European languages are a language family native to the overwhelming majority of Europe, the Iranian plateau, and the northern Indian subcontinent. Some European languages of this family, English, French, Portuguese, Russian, Dutch ...

. The word "resin" has been applied in the modern world to nearly any component of a liquid that will set into a hard

lacquer Lacquer is a type of hard and usually shiny coating or finish applied to materials such as wood or metal. It is most often made from resin extracted from trees and waxes and has been in use since antiquity. Asian lacquerware, which may be ca ...

or enamel-like finish. An example is nail polish. Certain "casting resins" and synthetic resins (such as

epoxy resin Epoxy is the family of basic components or cured end products of epoxy resins. Epoxy resins, also known as polyepoxides, are a class of reactive prepolymers and polymers which contain epoxide groups. The epoxide functional group is also coll ...

) have also been given the name "resin". Some naturally-derived resins, when soft, are known as 'oleoresins', and when containing

benzoic acid Benzoic acid is a white (or colorless) solid organic compound with the formula , whose structure consists of a benzene ring () with a carboxyl () substituent. It is the simplest aromatic carboxylic acid. The name is derived from gum benzoin, wh ...

or cinnamic acid they are called balsams. Oleoresins are naturally-occurring mixtures of an oil and a resin; they can be extracted from various plants. Other resinous products in their natural condition are a mix with gum or mucilaginous substances and known as gum resins. Several natural resins are used as ingredients in perfumes, e.g., balsams of Peru and tolu, elemi, styrax, and certain turpentines.

Non-resinous exudates

Other liquid compounds found inside plants or exuded by plants, such as

sap Sap is a fluid transported in xylem cells (vessel elements or tracheids) or phloem sieve tube elements of a plant. These cells transport water and nutrients throughout the plant. Sap is distinct from latex, resin, or cell sap; it is a separa ...

,

latex Latex is an emulsion (stable dispersion) of polymer microparticles in water. Latexes are found in nature, but synthetic latexes are common as well. In nature, latex is found as a milky fluid found in 10% of all flowering plants (angiosperms ...

, or mucilage, are sometimes confused with resin but are not the same. Saps, in particular, serve a nutritive function that resins do not. Résine

Uses

Plant resins

Plant resins are valued for the production of

varnish Varnish is a clear transparent hard protective coating or film. It is not a stain. It usually has a yellowish shade from the manufacturing process and materials used, but it may also be pigmented as desired, and is sold commercially in various ...

es,

adhesive Adhesive, also known as glue, cement, mucilage, or paste, is any non-metallic substance applied to one or both surfaces of two separate items that binds them together and resists their separation. The use of adhesives offers certain advant ...

s, and food

glazing agent A glazing agent is a natural or synthetic substance that provides a waxy, homogeneous, coating to prevent water loss from a surface and provide other protection. Natural Natural glazing agents keep moisture inside plants and insects. Scientists ...

s. They are also prized as raw materials for the synthesis of other organic compounds and provide constituents of

incense Incense is aromatic biotic material that releases fragrant smoke when burnt. The term is used for either the material or the aroma. Incense is used for aesthetic reasons, religious worship, aromatherapy, meditation, and ceremony. It may also be ...

and

perfume Perfume (, ; french: parfum) is a mixture of fragrant essential oils or aroma compounds (fragrances), fixatives and solvents, usually in liquid form, used to give the human body, animals, food, objects, and living-spaces an agreeable scent. Th ...

. The oldest known use of plant resin comes from the late Middle Stone Age in Southern Africa where it was used as an adhesive for hafting stone tools. Protium Sp

The hard transparent resins, such as the copals, dammars, mastic, and

sandarac Sandarac (or sandarach) is a resin obtained from the small cypress-like tree ''Tetraclinis articulata''. The tree is native to the northwest of Africa with a notable presence in the Southern Morocco part of the Atlas mountains. The resin exudes n ...

, are principally used for varnishes and adhesives, while the softer odoriferous oleo-resins (

frankincense Frankincense (also known as olibanum) is an aromatic resin used in incense and perfumes, obtained from trees of the genus ''Boswellia'' in the family Burseraceae. The word is from Old French ('high-quality incense'). There are several species o ...

,

elemi ''Canarium luzonicum'', commonly known as elemi, is a tree native to the Philippines. The oleoresin harvested from it is also known as elemi. Synonyms * ''Canarium carapifolium'' G.Perkins * ''Canarium oliganthum'' Merr. * ''Canarium polyanthu ...

,

turpentine Turpentine (which is also called spirit of turpentine, oil of turpentine, terebenthene, terebinthine and (colloquially) turps) is a fluid obtained by the distillation of resin harvested from living trees, mainly pines. Mainly used as a special ...

,

copaiba Copaiba is a stimulant oleoresin obtained from the trunk of several pinnate-leaved South American leguminous trees (genus ''Copaifera''). The thick, transparent exudate varies in color from light gold to dark brown, depending on the ratio of resi ...

), and gum resins containing essential oils (

ammoniacum Ammoniacum or the gum ammoniac is a gum-resin exuded from the several perennial herbs in the genus ''Ferula'' of the umbel family (Apiaceae). There are three types of ammoniacum: the gums ammoniac of Cyrenaica, of Persia (the commercial one today ...

, asafoetida,

gamboge Gamboge ( , ) is a partially transparent deep saffron to mustard yellow pigment.Other forms and spellings are: cambodia, cambogium, camboge, cambugium, gambaugium, gambogia, gambozia, gamboidea, gambogium, gumbouge, gambouge, gamboge, gambooge, g ...

,

myrrh Myrrh (; from Semitic, but see '' § Etymology'') is a gum-resin extracted from a number of small, thorny tree species of the genus ''Commiphora''. Myrrh resin has been used throughout history as a perfume, incense and medicine. Myrrh mi ...

, and

scammony ''Convolvulus scammonia'', known commonly as scammony, is a bindweed native to the countries of the eastern part of the Mediterranean basin; it grows in bushy waste places, from Syria in the south to the Crimea in the north, its range extending w ...

) are more used for therapeutic purposes, food and

incense Incense is aromatic biotic material that releases fragrant smoke when burnt. The term is used for either the material or the aroma. Incense is used for aesthetic reasons, religious worship, aromatherapy, meditation, and ceremony. It may also be ...

. The resin of the

Aleppo Pine ''Pinus halepensis'', commonly known as the Aleppo pine, also known as the Jerusalem pine, is a pine native to the Mediterranean region. Description ''Pinus halepensis'' is a small to medium-sized tree, tall, with a trunk diameter up to , exce ...

is used to flavour retsina, a Greek

resinated wine Resinated wine is a type of wine which derives part of its flavor from exposure to tree resins, most generally pine resin, therefore often being known as pine wine. Prior to the widespread use of barrels in Europe, wine was stored in amphorae, of ...

.

Synthetic resins

Many materials are produced via the conversion of synthetic resins to solids. Important examples are bisphenol A diglycidyl ether, which is a resin converted to epoxy glue upon the addition of a hardener. Silicones are often prepared from silicone resins via

room temperature vulcanization In a building or large vehicle, like a ship, a room is any enclosed space within a number of walls to which entry is possible only via a door or other dividing structure that connects it to either a passageway, another room, or the outdoors, that ...

. Alkyd resins are used in

paint Paint is any pigmented liquid, liquefiable, or solid mastic composition that, after application to a substrate in a thin layer, converts to a solid film. It is most commonly used to protect, color, or provide texture. Paint can be made in many ...

s and

varnish Varnish is a clear transparent hard protective coating or film. It is not a stain. It usually has a yellowish shade from the manufacturing process and materials used, but it may also be pigmented as desired, and is sold commercially in various ...

es and harden or cure by exposure to

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ...

in the air.

References

External links

* * {{Authority control Non-timber forest products Papermaking Tree tapping

Composition

Examples

Rosin

Petroleum- and insect-derived resins

History and etymology

Non-resinous exudates

Uses

Plant resins

Synthetic resins

See also

References

External links