3M - My reflections on the learning journey
3M Products that interest me
Cyanoacrylate adhesives
One set of products which is strongly associated with 3M are the adhesives, and 3M dazzles me with its wide range of adhesives for different purposes. From Scotch-Weld instant adhesives that can bond with up to two tonnes of holding power to the adhesive on Post-It notes that only hold on to surfaces weakly, the multitude of products cater to different needs.
My research would be on the cyanoacrylates found in Scotch-Weld instant adhesives and the chemistry behind such powerful adhesion.
Cyanoacrylate is the generic name for cyanoacrylate based fast-acting adhesives such as methyl 2-cyanoacrylate, ethyl-2-cyanoacrylate, and n-butyl cyanoacrylate. It is an acrylic resin that cures (or forms its strongest bond) almost instantly in the presence of hydroxide ions from water.
The hydroxide ions act as nucleophiles (Nu-) initiates the reaction by attacking the C=C double bond, which breaks and forms a new bond with the nucleophile on one side of the double-bond, and forms the anion on the other side because nothing else adds onto the other side of the double-bond.
The anion formed attacks another cyanoacrylate monomer at the C=C double-bond, forming another anion. The reaction continues until it is terminated by the presence of water and air that react and "quench" the nucleophile.
Since almost any surface that the glue is applied on has water molecules, when the glue is applied, the monomers start linking up into chains and these chains start whipping around to form a durable plastic mesh. The glue thickens and hardens until the thrashing molecule strands can no longer move.
The picture on top shows the polymerisation of methyl 2-cyanoacrylate.
Though this adhesive was invented by Dr. Harry Coover for Kodak Laboratories in 1949, 3M has filed many patents on improvements to create the wide range of cyanoacrylate adhesives that it sells for different uses, such as including tougheners (core-shell copolymers such as MBS) and sustainers (organic compounds containing one or more aryl groups, such as diphenylmethane).
References:
http://www.chm.bris.ac.uk/motm/superglue/superglueh.htm
http://home.earthlink.net/~djndan/Articles/CA%20FAQs.pdf
http://www.howstuffworks.com/question695.htm
http://www.google.com/patents?id=kQwwAAAAEBAJ&printsec=abstract&zoom=4&source=gbs_overview_r&cad=0#v=onepage&q&f=falsehttp://multimedia.3m.com/mws/mediawebserver?mwsId=66666UuZjcFSLXTtnxM_4XfXEVuQEcuZgVs6EVs6E666666--&fn=78-9236-7153-7%20HR.pdf
Though this adhesive was invented by Dr. Harry Coover for Kodak Laboratories in 1949, 3M has filed many patents on improvements to create the wide range of cyanoacrylate adhesives that it sells for different uses, such as including tougheners (core-shell copolymers such as MBS) and sustainers (organic compounds containing one or more aryl groups, such as diphenylmethane).
References:
http://www.chm.bris.ac.uk/motm/superglue/superglueh.htm
http://home.earthlink.net/~djndan/Articles/CA%20FAQs.pdf
http://www.howstuffworks.com/question695.htm
http://www.google.com/patents?id=kQwwAAAAEBAJ&printsec=abstract&zoom=4&source=gbs_overview_r&cad=0#v=onepage&q&f=falsehttp://multimedia.3m.com/mws/mediawebserver?mwsId=66666UuZjcFSLXTtnxM_4XfXEVuQEcuZgVs6EVs6E666666--&fn=78-9236-7153-7%20HR.pdf
Privacy filters
Besides adhesives, another lesser-known product 3M makes are privacy filters for notebooks, tablets and other electronic devices. As stated in the 3M website "3M "microlouver technology" within the film structure reduces the horizontal viewing area of the LCD to 60 degrees. Persons directly in front of the display have an unobstructed view of displayed information. But from either side, passersby or casual observers see a dark, blank screen. The privacy film technology provides a second, equally beneficial function by shielding out unwanted ambient light, thus incrementally increasing the effectiveness of glare reduction and contrast enhancement."
The privacy screen consists of a number of closely-spaced partitions or louvers, which selectively block the transmission of light depending upon the angle at which light strikes the film surface. The louvers are angled perpendicular to the surface of the film, and thus maximum transmission occurs in the perpendicular direction. The louvers are composed of agglomerates of small particles of optically limiting material, which may be substantially opaque particles to block transmission. The louvered film is then coated with a solventless composition of an oligomer, a monomer, and a photo-initiator, which polymerises to a clear, hard layer upon exposure to certain types of radiation, forming a louvered plastic film.
Besides adhesives, another lesser-known product 3M makes are privacy filters for notebooks, tablets and other electronic devices. As stated in the 3M website "3M "microlouver technology" within the film structure reduces the horizontal viewing area of the LCD to 60 degrees. Persons directly in front of the display have an unobstructed view of displayed information. But from either side, passersby or casual observers see a dark, blank screen. The privacy film technology provides a second, equally beneficial function by shielding out unwanted ambient light, thus incrementally increasing the effectiveness of glare reduction and contrast enhancement."
The privacy screen consists of a number of closely-spaced partitions or louvers, which selectively block the transmission of light depending upon the angle at which light strikes the film surface. The louvers are angled perpendicular to the surface of the film, and thus maximum transmission occurs in the perpendicular direction. The louvers are composed of agglomerates of small particles of optically limiting material, which may be substantially opaque particles to block transmission. The louvered film is then coated with a solventless composition of an oligomer, a monomer, and a photo-initiator, which polymerises to a clear, hard layer upon exposure to certain types of radiation, forming a louvered plastic film.
References
http://www.google.com/patents?id=feshAAAAEBAJ&printsec=abstract&zoom=4&source=gbs_overview_r&cad=0#v=onepage&q&f=falsehttp://www.google.com/patents?id=BgcSAAAAEBAJ&printsec=abstract&zoom=4&source=gbs_overview_r&cad=0#v=onepage&q&f=false
http://www.google.com/patents?id=Rt84AAAAEBAJ&printsec=abstract&source=gbs_overview_r&cad=0#v=onepage&q&f=false
http://solutions.3m.com/wps/portal/3M/en_US/SDP/Privacy_Filters/Solutions/One/
http://www.google.com/patents?id=feshAAAAEBAJ&printsec=abstract&zoom=4&source=gbs_overview_r&cad=0#v=onepage&q&f=falsehttp://www.google.com/patents?id=BgcSAAAAEBAJ&printsec=abstract&zoom=4&source=gbs_overview_r&cad=0#v=onepage&q&f=false
http://www.google.com/patents?id=Rt84AAAAEBAJ&printsec=abstract&source=gbs_overview_r&cad=0#v=onepage&q&f=false
http://solutions.3m.com/wps/portal/3M/en_US/SDP/Privacy_Filters/Solutions/One/