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=== Gorenje ===
=== Gorenje ===
Pri gorenju silikonov v prisotnosti zraka ali kisika se v obliki belega prahu sprošča trden silicijev dioksid (SiO<sub>2</sub>) v amorfni obliki (angl. ''silica fume''). Piroliza nekaterih polisiloksanov v inertni atmosferi je začetek sintezne poti, po kateri proizvajamo amorfno oksikarbidno keramiko (angl. ''silicon oxycarbide ceramics'', tudi ''polymer derived ceramics (PDCs)''). Polisiloksani z vinilno, tiolno ali akrilatno funkcionalno skupino na koncu verige pa reagirajo do zamreženih polimerov (prekurzorji za tvorbo keramičnih spojin (PDC-jev); angl. ''preceramic polymers''), iz katerih s postopkom fotopolimerizacije dobimo materiale, ki se uporabljajo za 3D-tiskanje s pomočjo stereolitografskih tehnik. <ref>[https://arxiv.org/ftp/arxiv/papers/1905/1905.02060.pdf  Additive manufacturing of ceramics from preceramic polymers]: A versatile stereolithographic approach assisted by thiol-ene click chemistry. ''Additive Manufacturing'', (2019) volume 27, pp. 80–90.</ref>
Pri gorenju silikonov v prisotnosti zraka ali kisika se v obliki belega prahu sprošča trden silicijev dioksid (SiO<sub>2</sub>) v amorfni obliki (angl. ''silica fume''). Piroliza nekaterih polisiloksanov v inertni atmosferi je začetek sintezne poti, po kateri proizvajamo amorfno oksikarbidno keramiko (angl. ''silicon oxycarbide ceramics'', tudi ''polymer derived ceramics (PDCs)''). Polisiloksani z vinilno, tiolno ali akrilatno funkcionalno skupino na koncu verige pa reagirajo do zamreženih polimerov (prekurzorji za tvorbo keramičnih spojin (PDC-jev); angl. ''preceramic polymers''), iz katerih s postopkom fotopolimerizacije dobimo materiale, ki se uporabljajo za 3D-tiskanje s pomočjo stereolitografskih tehnik. <ref>[https://arxiv.org/ftp/arxiv/papers/1905/1905.02060.pdf  Additive manufacturing of ceramics from preceramic polymers]: A versatile stereolithographic approach assisted by thiol-ene click chemistry. ''Additive Manufacturing'', (2019) volume 27, pp. 80–90.</ref>
=== Protipožarna zaščita ===
Silikonska pena je v uporabi v severnoameriških stavbah z namenom preprečitve širjenja ognja in dima iz ene sobe v drugo skozi odprtine v ognjevarnih stenskih in talnih sklopih. Če je pravilno nameščena, je požarno zaščito iz silikonske pene mogoče izdelati povsem v skladu z gradbenimi predpisi. Prednosti silikonskih pen sta fleksibilnost in visoka dielektrična trdnost, pomanjkljivosti pa vnetljivost (oteženo gašenje) in pospešena tvorba dima.
Protipožarne zaščite iz silikonske pene so bile predmet polemike in deležne precejšnje medijske pozornosti zaradi nastajanja dima pri sežigu gorljivih komponent v peni, izhajanja vodika, krčenja in nastajanja razpok. Zaradi teh težav in z njimi povezanih dogodkov so bili pogosto obveščeni tudi upravljalci jedrskih elektrarn kot licencirani člani Komisije za jedrsko regulativo (NRC).
Silikonske požarne zaščite pa se uporabljajo tudi v letalih.
=== Nakit ===
Silikon je pri izdelovanju nakita, zlasti prstanov, priljubljena alternativa tradicionalnim kovinam, kot sta srebro in zlato. Silikonske prstane pogosto nosijo delavci v poklicih, kjer lahko kovinski prstani povzročijo poškodbe zaradi električne prevodnosti. <ref>{{Cite web|url=https://ourorganicwedding.com/silicone-ring-trend/|title=Is the Silicone Ring Trend Here to Stay?|first=Sarah|last=Ashley|date=August 1, 2018}}</ref><ref>{{Cite web|url=https://www.insider.com/guides/silicone-wedding-ring-trend-2017-10|title=A ton of couples are skipping the fancy wedding rings and opting for these $20 rubber bands instead — here's why|first=Connie|last=Chen|website=Insider}}</ref> Od sredine prejšnjega desetletja so nekateri profesionalni športniki med tekmami začeli nositi silikonske prstane kot alternativo pravim.<ref>{{Cite web|url=https://www.espn.com/blog/detroit-lions/post/_/id/25500/the-wedding-rings-the-thing-silicone-bands-growing-trend-in-nfl|title=The (wedding) ring's the thing: Silicone bands a growing trend in NFL|date=September 29, 2016|website=ESPN.com}}</ref>
=== Lubricants ===
[[File:Laboratory grease 1.jpg|thumb|Silicone grease is often used with laboratory glassware to prevent seizing.]]
Silicone [[grease (lubricant)|grease]]s are used for many purposes, such as [[bicycle chain]]s, [[airsoft gun]] parts, and a wide range of other [[Mechanism (engineering)|mechanisms]]. Typically, a dry-set lubricant is delivered with a solvent carrier to penetrate the mechanism. The solvent then evaporates, leaving a clear film that lubricates but does not attract dirt and grit as much as an [[oil]]-based or other traditional "wet" lubricant.
Silicone [[personal lubricant]]s are also available for use in medical procedures or sexual activity.
=== Medicine and cosmetic surgery ===
Silicone is used in [[microfluidics]], seals, gaskets, shrouds, and other applications requiring high [[biocompatibility]]. Additionally, the gel form is used in bandages and dressings, [[Silicone gel-filled breast implants|breast implants]], testicle implants, pectoral implants, [[Contact lens#Silicone Hydrogel Lenses|contact lenses]], and a variety of other medical uses.
[[silicone scar sheet|Scar treatment sheets]] are often made of [[medical grade silicone]] due to its durability and biocompatibility. [[Polydimethylsiloxane|Polydimethylsiloxane (PDMS)]] is often used for this purpose, since its specific crosslinking results in a flexible and soft silicone with high durability and tack. It has also been used as the hydrophobic block of [[amphiphilic]] synthetic block [[copolymers]] used to form the vesicle membrane of [[polymersome]]s.
Illicit cosmetic silicone injections may induce chronic and definitive silicone blood diffusion with dermatologic complications.<ref>{{Cite journal|url=https://journals.lww.com/md-journal/fulltext/2019/01250/Illicit_massive_silicone_injections_always_induce.28.aspx|title=Illicit massive silicone injections always induce chronic and definitive silicone blood diffusion with dermatologic complications|first1=Chloé|last1=Bertin|first2=Rachid|last2=Abbas|first3=Valérie|last3=Andrieu|first4=Florence|last4=Michard|first5=Christophe|last5=Rioux|first6=Vincent|last6=Descamps|first7=Yazdan|last7=Yazdanpanah|first8=Fabrice|last8=Bouscarat|date=January 1, 2019|journal=Medicine|volume=98|issue=4|pages=e14143|via=journals.lww.com|doi=10.1097/MD.0000000000014143|pmid=30681578|pmc=6358378}}</ref>
Ophthalmology uses many products such as silicone oil used to replace the [[vitreous humor]] following vitrectomy, silicone intraocular lenses following cataract extraction, silicone tubes to keep a nasolacrimal passage open following dacryocystorhinostomy, canalicular stents for canalicular stenosis, punctual plugs for punctual occlusion in dry eyes, silicone rubber and bands as an external [[tamponade]] in tractional retinal detachment, and anteriorly-located break in rhegmatogenous retinal detachment.
Addition and condensation (e.g. [[polyvinyl siloxane]]) silicones find wide application as a [[dental impression]] material due to its hydrophobic property and thermal stability.<ref>{{Cite web |date=July 19, 2022 |title=The many uses of dental impression silicone |url=https://magazine.zhermack.com/en/laboratory-en/many-uses-of-dental-impression-silicone/ |access-date=January 16, 2023}}</ref><ref>{{Cite book |last=Ferracane |first=Jack L. |url=https://www.worldcat.org/oclc/45604030 |title=Materials in dentistry : principles and applications |date=2001 |publisher=Lippincott Williams & Wilkins |isbn=0-7817-2733-2 |edition=2nd |location=Philadelphia |oclc=45604030}}</ref><ref>{{Cite book |url=https://www.worldcat.org/oclc/1124496192 |title=Sturdevant's art and science of operative dentistry. |date=2018 |others=André V. Ritter, Clifford M. Sturdevant |isbn=978-0-323-47858-8 |edition=7 |location=St. Louis |oclc=1124496192}}</ref>
=== Moldmaking ===
[[File:Silicone mold.jpg|thumb|Silicone mold used to reproduce an architectural detail]]
Two-part silicone systems are used as rubber molds to cast [[resin casting|resins]], foams, rubber, and low-temperature alloys. A silicone mold generally requires little or no mold-release or surface preparation, as most materials do not adhere to silicone. For experimental uses, ordinary one-part silicone can be used to make molds or to mold into shapes. If needed, common [[cooking oil|vegetable cooking oils]] or [[petroleum jelly]] can be used on mating surfaces as a mold-release agent.<ref>Robyn Lish. [https://www.glasstradecentre.com.au/2020/04/08/what-are-the-benefits-of-silicone-caulk-moulds/ What are the benefits of Silicone Caulk Moulds]. Myheap.com. Retrieved on 2021-08-08.</ref>
Silicone cooking molds used as [[bakeware]] do not require coating with cooking oil; in addition, the flexibility of the rubber allows the baked food to be easily removed from the mold after cooking.
=== Personal care ===
[[File:Musicians orange plugs.jpg|thumb|Silicone rubber earplugs for hearing protection]]
Silicones are ingredients widely used in skincare, color cosmetic and hair care applications. Some silicones, notably the [[amine]] functionalized amodimethicones, are excellent hair conditioners, providing improved compatibility, feel, and softness, and lessening frizz. The phenyl dimethicones, in another silicone family, are used in reflection-enhancing and color-correcting hair products, where they increase shine and glossiness (and possibly impart subtle color changes). Phenyltrimethicones, unlike the conditioning amodimethicones, have refractive indices (typically 1.46) close to that of a human hair (1.54). However, if included in the same formulation, amodimethicone and phenyltrimethicone interact and dilute each other, making it difficult to achieve both high shine and excellent conditioning in the same product.<ref>Thomas Clausen et al. "Hair Preparations" in ''Ullmann's Encyclopedia of Industrial Chemistry'', 2007, Wiley-VCH, Weinheim. {{doi|10.1002/14356007.a12_571.pub2}}</ref>
Silicone rubber is commonly used in [[baby bottle]] nipples (teats) for its cleanliness, aesthetic appearance, and low extractable content.
Silicones are used in [[shaving|shaving products]] and [[personal lubricants]].<ref>Q. Ashton Acton: ''Silicones—Advances in Research and Application: 2013 Edition'', ScholarlyEditions, 2013, {{ISBN|9781481692397}}, [https://books.google.com/books?id=ZxzUfxVh6uEC&pg=PA226 p. 226] {{webarchive|url=https://web.archive.org/web/20171218190618/https://books.google.com/books?id=ZxzUfxVh6uEC&pg=PA226 |date=2017-12-18 }}.</ref>

Revision as of 15:43, 19 May 2023

Silikon (tudi polisiloksan) je polimer siloksana (−R2Si−O−SiR2−, kjer R predstavlja organsko stransko skupino). Silikonski materiali (silikoni) se pojavljajo v obliki brezbarvnih olj ali gumi podobnih snovi ter kot masti in smole. Najpogosteje se uporabljajo v vlogi tesnil, materialov za lepljenje, maziv, medicinskih in kuhinjskih pripomočkov ter toplotnih in električnih izolatorjev.<ref name=Ullmann/><ref>Template:Cite book</ref>

Kemija

Stock in Somieski sta med preučevanjem reakcije hidrolize diklorosilana ugotovila, da se pri reakciji tvori monomer siloksana H2SiO:

SiH2Cl2 + H2O -> H2SiO + 2 HCl.

Hidrolizo lahko izvajamo tako, da raztopini diklorosilana v benzenu dodajamo vodo. V tem primeru je večinski produkt polimer s približno formulo [H2SiO]6, verjetno pa se pri daljšem času izvajanja reakcije tvorijo tudi daljši polimeri.<ref name="Seyferth">Seyferth, D., Prud'Homme, C., Wiseman, G., Cyclic Polysiloxanes from the Hydrolysis of Dichlorosilane, Inorganic Chemistry, 22, 2163-2167</ref>

Osnova vseh polisiloksanov je veriga, v kateri se izmenjujeta silicijev in kisikov atom (…–Si–O–Si–O–Si–O–…) in je včasih sklenjena v krog. Na vsakega izmed silicijevih atomov sta vezani dve stranski skupini, ki sta največkrat organska substituenta – primer takšnih polimerov sta [(CH3)2SiO]n in [(C6H5)2SiO)]n. Med proizvodnjo silikonov lahko s spreminjanjem dolžine polimerov, stranskih skupin in stopnje zamreženosti sintetiziramo snovi z izjemno raznolikimi lastnostmi, o d tekočin in gelov do mehke gume in trdnih materialov s plastičnimi lastnostmi. Najosnovnejši polisiloksan je linearni polidimetilsiloksan (PDMS), ki je pri sobnih pogojih v tekočem agregatnem stanju. Zelo velika skupina silikonskih materialov so silikonske smole, ki so sestavljene iz zamreženih polimerov, katerih struktura spominja na kletko.

Terminologija in zgodovina

Beseda silikon (angl. silicone), ki jo je leta 1901 vpeljal Frederic Stanley Kipping, je nastala kot krajše ime za polidifenilsiloksan ([Ph2SiO]n). Pri tem se je zgledoval po ketonu benzofenonu (Ph2CO), katerega je poimenoval silikoketon (angl. silicoketone). Kljub takšni analogiji pa je Kipping s preučevanjem lastnosti obeh spojin pokazal, da je benzofenon monomerna molekula, polidifenilsiloksan pa polimer, kar pomeni, da silikon ni popolnoma ustrezno poimenovanje.<ref>Template:Greenwood&Earnshaw2nd</ref><ref>Template:Cite journal</ref> Ker je bilo dokazano, da je strukturno polidifenilsiloksan bistveno drugačen od benzofenona, bi bilo glede na kemijsko nomenklaturo namesto silikon bolj ustrezno uporabljati poimenovanje siloksan, vendar se ta sprememba nikoli ni uveljavila, zato je izraz silikon v uporabi še danes. <ref name="CincinnatiUniversity2005">Template:Cite book</ref>

Ameriški kemik in izumitelj James Franklin Hyde (rojen 11. marca 1903) je znan pod imenom “Oče silikonov”, saj je v tridesetih letih prejšnjega stoletja ključno prispeval k začetku industrije silikonov. Njegovi najpomembnejši odkritji sta sinteza silikonov iz silicijevih spojin ter razvoj metode za pripravo taljenega silicijevega dioksida (angl. fused silica), kremenovega stekla, ki ga danes med drugim uporabljamo na področjih aeronavtike, telekomunikacij in proizvodnje računalniških čipov. Kot rezultat njegovega dela sta se podjetji Dow Chemical Company in Corning Glass Works povezali v zvezo Dow Corning, katere namen je bil proizvodnja izdelkov iz silikona.

Občasno prihaja do zamenjave izrazov silikon (angl. silicone) in silicij (angl. silicon), čeprav gre za dve kemijsko popolnoma različni snovi. Silicij je kemijski element, in sicer trda temnosiva polkovina. Kristali silicija izkazujejo polprevodniške lastnosti, zaradi česar so ključnega pomena za izdelavo čipov in sončnih celic. V primeru silikona pa gre za molekulske snovi, ki jih večinoma gradijo atomi silicija, kisika, ogljika in vodika, in imajo zaradi različnih molekulskih struktur tudi izjemno raznolike fizikalne in kemijske lastnosti.

Še ena skupina silicijevih spojin, ki bi jih lahko označili za silikone, so silanoni, za katere je značilno, da v svoji molekulski strukturi vsebujejo vsaj eno dvojno kovalentno vez, ki povezuje silicijev in kisikov atom. Silanoni so bili že dolgo znani kot intermediati v kemijskih reakcijah, ki potekajo med plini, na primer v procesu kemičnega naparjevanja (angl. chemical vapour deposition, CVD), ki je korak v proizvodnji mikroelektronskih elementov, in žganja keramike.<ref>Template:Cite journal</ref> Lastnost silanonov je spontana in hitra reakcija (polimerizacija) do siloksanov. Prvi, ki je leta 2014 sintetiziral stabilen silanon, je bil Alexander C. Filippou s sodelavci.<ref name=filippou>Alexander C. Filippou, Bernhard Baars, Yury N. Lebedev, and Gregor Schnakenburg (2014): "Silicon–Oxygen Double Bonds: A Stable Silanone with a Trigonal‐Planar Coordinated Silicon Center". Angewandte Chemie International Edition, volume 53, issue 2, pages 565–570. Template:Doi.</ref>


Sinteza

Najpogosteje so silikoni sintetizirani iz polidimetilsiloksana, ki nastane kot produkt reakcije hidrolize dimetildiklorosilana:

n Si(CH3)2Cl2 + n H2O → [Si(CH3)2O]n + 2n HCl

Z reakcijo polimerizacije navadno nastanejo verižni polimeri, ki se zaključijo tako, da je na terminalni atom silicija vezan klorov atom (Si–Cl) ali hidroksilna skupina (Si–OH - funkcionalna skupina Si–OH se imenuje tudi silanolna skupina). Če sintezo izvajamo pod drugačnimi reakcijskimi pogoji, lahko kot produkt dobimo tudi ciklične polimere, pri katerih se osnovna veriga silicijevih in kisikovih atomov sklene v krog.<ref name=Ullmann/>

Za množično proizvodnjo potrošniških izdelkov so namesto silil kloridov izhodne spojine pogosto silil acetati. Razlog za takšno izbiro reaktantov je, da kot stranski produkt namesto klorovodikove kisline dobimo manj nevarno ocetno kislino, ki jo med drugim najdemo v kisu. Takšna sinteza poteka počasneje, uporablja pa se za proizvodnjo izdelkov, kot so silikonska tesnila in lepila:

n Si(CH3)2(CH3COO)2 + n H2O → [Si(CH3)2O]n + 2n CH3COOH

Če želimo kot produkte dobiti razvejane in zamrežene silikone, moramo kot prekurzorje uporabiti organosilicijeve spojine z manjšim številom alkilnih skupin, kot sta na primer metiltriklorosilan in metiltrimetoksisilan, ki pri idealnem poteku reakcije ustvarijo nova razvejišča na osnovni verigi silikona. Na takšen način potekajo sinteze trših silikonskih smol. Če pa je cilj sinteze proizvodnja silikonov z omejeno molekulsko maso, moramo pri reakciji uporabiti reaktante, ki imajo na treh mestih vezano nereaktivno skupino, kakršna je na primer metilna skupina, tako da lahko silicij tekom reakcije tvori zgolj eno novo kemijsko vez.

Gorenje

Pri gorenju silikonov v prisotnosti zraka ali kisika se v obliki belega prahu sprošča trden silicijev dioksid (SiO2) v amorfni obliki (angl. silica fume). Piroliza nekaterih polisiloksanov v inertni atmosferi je začetek sintezne poti, po kateri proizvajamo amorfno oksikarbidno keramiko (angl. silicon oxycarbide ceramics, tudi polymer derived ceramics (PDCs)). Polisiloksani z vinilno, tiolno ali akrilatno funkcionalno skupino na koncu verige pa reagirajo do zamreženih polimerov (prekurzorji za tvorbo keramičnih spojin (PDC-jev); angl. preceramic polymers), iz katerih s postopkom fotopolimerizacije dobimo materiale, ki se uporabljajo za 3D-tiskanje s pomočjo stereolitografskih tehnik. <ref>Additive manufacturing of ceramics from preceramic polymers: A versatile stereolithographic approach assisted by thiol-ene click chemistry. Additive Manufacturing, (2019) volume 27, pp. 80–90.</ref>

Protipožarna zaščita

Silikonska pena je v uporabi v severnoameriških stavbah z namenom preprečitve širjenja ognja in dima iz ene sobe v drugo skozi odprtine v ognjevarnih stenskih in talnih sklopih. Če je pravilno nameščena, je požarno zaščito iz silikonske pene mogoče izdelati povsem v skladu z gradbenimi predpisi. Prednosti silikonskih pen sta fleksibilnost in visoka dielektrična trdnost, pomanjkljivosti pa vnetljivost (oteženo gašenje) in pospešena tvorba dima.

Protipožarne zaščite iz silikonske pene so bile predmet polemike in deležne precejšnje medijske pozornosti zaradi nastajanja dima pri sežigu gorljivih komponent v peni, izhajanja vodika, krčenja in nastajanja razpok. Zaradi teh težav in z njimi povezanih dogodkov so bili pogosto obveščeni tudi upravljalci jedrskih elektrarn kot licencirani člani Komisije za jedrsko regulativo (NRC).

Silikonske požarne zaščite pa se uporabljajo tudi v letalih.

Nakit

Silikon je pri izdelovanju nakita, zlasti prstanov, priljubljena alternativa tradicionalnim kovinam, kot sta srebro in zlato. Silikonske prstane pogosto nosijo delavci v poklicih, kjer lahko kovinski prstani povzročijo poškodbe zaradi električne prevodnosti. <ref></ref><ref></ref> Od sredine prejšnjega desetletja so nekateri profesionalni športniki med tekmami začeli nositi silikonske prstane kot alternativo pravim.<ref></ref>

Lubricants

File:Laboratory grease 1.jpg
Silicone grease is often used with laboratory glassware to prevent seizing.

Silicone greases are used for many purposes, such as bicycle chains, airsoft gun parts, and a wide range of other mechanisms. Typically, a dry-set lubricant is delivered with a solvent carrier to penetrate the mechanism. The solvent then evaporates, leaving a clear film that lubricates but does not attract dirt and grit as much as an oil-based or other traditional "wet" lubricant.

Silicone personal lubricants are also available for use in medical procedures or sexual activity.

Medicine and cosmetic surgery

Silicone is used in microfluidics, seals, gaskets, shrouds, and other applications requiring high biocompatibility. Additionally, the gel form is used in bandages and dressings, breast implants, testicle implants, pectoral implants, contact lenses, and a variety of other medical uses.

Scar treatment sheets are often made of medical grade silicone due to its durability and biocompatibility. Polydimethylsiloxane (PDMS) is often used for this purpose, since its specific crosslinking results in a flexible and soft silicone with high durability and tack. It has also been used as the hydrophobic block of amphiphilic synthetic block copolymers used to form the vesicle membrane of polymersomes.

Illicit cosmetic silicone injections may induce chronic and definitive silicone blood diffusion with dermatologic complications.<ref>Template:Cite journal</ref>

Ophthalmology uses many products such as silicone oil used to replace the vitreous humor following vitrectomy, silicone intraocular lenses following cataract extraction, silicone tubes to keep a nasolacrimal passage open following dacryocystorhinostomy, canalicular stents for canalicular stenosis, punctual plugs for punctual occlusion in dry eyes, silicone rubber and bands as an external tamponade in tractional retinal detachment, and anteriorly-located break in rhegmatogenous retinal detachment.

Addition and condensation (e.g. polyvinyl siloxane) silicones find wide application as a dental impression material due to its hydrophobic property and thermal stability.<ref></ref><ref>Template:Cite book</ref><ref>Template:Cite book</ref>

Moldmaking

File:Silicone mold.jpg
Silicone mold used to reproduce an architectural detail

Two-part silicone systems are used as rubber molds to cast resins, foams, rubber, and low-temperature alloys. A silicone mold generally requires little or no mold-release or surface preparation, as most materials do not adhere to silicone. For experimental uses, ordinary one-part silicone can be used to make molds or to mold into shapes. If needed, common vegetable cooking oils or petroleum jelly can be used on mating surfaces as a mold-release agent.<ref>Robyn Lish. What are the benefits of Silicone Caulk Moulds. Myheap.com. Retrieved on 2021-08-08.</ref>

Silicone cooking molds used as bakeware do not require coating with cooking oil; in addition, the flexibility of the rubber allows the baked food to be easily removed from the mold after cooking.

Personal care

File:Musicians orange plugs.jpg
Silicone rubber earplugs for hearing protection

Silicones are ingredients widely used in skincare, color cosmetic and hair care applications. Some silicones, notably the amine functionalized amodimethicones, are excellent hair conditioners, providing improved compatibility, feel, and softness, and lessening frizz. The phenyl dimethicones, in another silicone family, are used in reflection-enhancing and color-correcting hair products, where they increase shine and glossiness (and possibly impart subtle color changes). Phenyltrimethicones, unlike the conditioning amodimethicones, have refractive indices (typically 1.46) close to that of a human hair (1.54). However, if included in the same formulation, amodimethicone and phenyltrimethicone interact and dilute each other, making it difficult to achieve both high shine and excellent conditioning in the same product.<ref>Thomas Clausen et al. "Hair Preparations" in Ullmann's Encyclopedia of Industrial Chemistry, 2007, Wiley-VCH, Weinheim. Template:Doi</ref>

Silicone rubber is commonly used in baby bottle nipples (teats) for its cleanliness, aesthetic appearance, and low extractable content.

Silicones are used in shaving products and personal lubricants.<ref>Q. Ashton Acton: Silicones—Advances in Research and Application: 2013 Edition, ScholarlyEditions, 2013, Template:ISBN, p. 226 Template:Webarchive.</ref>