Noting that photo-polymerization rate is proportional to intensity<ref>{{Cite journal|last=Decker|first=Christian|date=1998-02-01|title=The use of UV irradiation in polymerization|url=|journal=Polymer International|language=en|volume=45|issue=2|pages=133–141 |doi=10.1002/(SICI)1097-0126(199802)45:2<133::AID-PI969>3.0.CO;2-F}}</ref> and that refractive index is proportional to molecular weight,<ref>{{Cite journal|last=Askadskii|first=A. A.|year=1990|title=Influence of crosslinking density on the properties of polymer networks|journal=Polymer Science U.S.S.R.|volume=32|issue=10|pages=2061–2069|doi=10.1016/0032-3950(90)90361-9}}</ref> the positive feedback between intensity and photo-polymerization establishes the auto-catalytic behavior. Optical auto-catalysis has been shown to result on spontaneous [[pattern formation]] in photopolymers.<ref>{{Cite journal|last=Burgess|first=Ian B.|last2=Shimmell|first2=Whitney E.|last3=Saravanamuttu|first3=Kalaichelvi|date=2007-04-01|title=Spontaneous Pattern Formation Due to Modulation Instability of Incoherent White Light in a Photopolymerizable Medium|journal=Journal of the American Chemical Society|volume=129|issue=15|pages=4738–4746|doi=10.1021/ja068967b|pmid=17378567|issn=0002-7863}}</ref><ref>{{Cite journal|last=Basker|first=Dinesh K.|last2=Brook|first2=Michael A.|last3=Saravanamuttu|first3=Kalaichelvi|title=Spontaneous Emergence of Nonlinear Light Waves and Self-Inscribed Waveguide Microstructure during the Cationic Polymerization of Epoxides|journal=The Journal of Physical Chemistry C|language=en|volume=119|issue=35|pages=20606–20617|doi=10.1021/acs.jpcc.5b07117|year=2015}}</ref><ref>{{Cite journal|last=Biria|first=Saeid|last2=Malley|first2=Philip P. A.|last3=Kahan|first3=Tara F.|last4=Hosein|first4=Ian D.|date=2016-03-03|title=Tunable Nonlinear Optical Pattern Formation and Microstructure in Cross-Linking Acrylate Systems during Free-Radical Polymerization|journal=The Journal of Physical Chemistry C|volume=120|issue=8|pages=4517–4528|doi=10.1021/acs.jpcc.5b11377|issn=1932-7447}}</ref> Hosein and co-workers discovered that optical autocatalysis can also occur in photoreactive polymer blends, and that the process can induce binary phase morphologies with the same pattern as the light profile.<ref name=":0" /> The light undergoes optical [[Modulational instability|modulation instability]], spontaneous dividing into a multitude of optical filaments, and the polymer system thereby forms filaments within the blend structure.<ref name=":0" /> The result is a new system that couples optical autocatalytic behavior to [[spinodal decomposition]]. | Noting that photo-polymerization rate is proportional to intensity<ref>{{Cite journal|last=Decker|first=Christian|date=1998-02-01|title=The use of UV irradiation in polymerization|url=|journal=Polymer International|language=en|volume=45|issue=2|pages=133–141 |doi=10.1002/(SICI)1097-0126(199802)45:2<133::AID-PI969>3.0.CO;2-F}}</ref> and that refractive index is proportional to molecular weight,<ref>{{Cite journal|last=Askadskii|first=A. A.|year=1990|title=Influence of crosslinking density on the properties of polymer networks|journal=Polymer Science U.S.S.R.|volume=32|issue=10|pages=2061–2069|doi=10.1016/0032-3950(90)90361-9}}</ref> the positive feedback between intensity and photo-polymerization establishes the auto-catalytic behavior. Optical auto-catalysis has been shown to result on spontaneous [[pattern formation]] in photopolymers.<ref>{{Cite journal|last=Burgess|first=Ian B.|last2=Shimmell|first2=Whitney E.|last3=Saravanamuttu|first3=Kalaichelvi|date=2007-04-01|title=Spontaneous Pattern Formation Due to Modulation Instability of Incoherent White Light in a Photopolymerizable Medium|journal=Journal of the American Chemical Society|volume=129|issue=15|pages=4738–4746|doi=10.1021/ja068967b|pmid=17378567|issn=0002-7863}}</ref><ref>{{Cite journal|last=Basker|first=Dinesh K.|last2=Brook|first2=Michael A.|last3=Saravanamuttu|first3=Kalaichelvi|title=Spontaneous Emergence of Nonlinear Light Waves and Self-Inscribed Waveguide Microstructure during the Cationic Polymerization of Epoxides|journal=The Journal of Physical Chemistry C|language=en|volume=119|issue=35|pages=20606–20617|doi=10.1021/acs.jpcc.5b07117|year=2015}}</ref><ref>{{Cite journal|last=Biria|first=Saeid|last2=Malley|first2=Philip P. A.|last3=Kahan|first3=Tara F.|last4=Hosein|first4=Ian D.|date=2016-03-03|title=Tunable Nonlinear Optical Pattern Formation and Microstructure in Cross-Linking Acrylate Systems during Free-Radical Polymerization|journal=The Journal of Physical Chemistry C|volume=120|issue=8|pages=4517–4528|doi=10.1021/acs.jpcc.5b11377|issn=1932-7447}}</ref> Hosein and co-workers discovered that optical autocatalysis can also occur in photoreactive polymer blends, and that the process can induce binary phase morphologies with the same pattern as the light profile.<ref name=":0" /> The light undergoes optical [[Modulational instability|modulation instability]], spontaneous dividing into a multitude of optical filaments, and the polymer system thereby forms filaments within the blend structure.<ref name=":0" /> The result is a new system that couples optical autocatalytic behavior to [[spinodal decomposition]]. |