very strong , and Modif. Epoxies Polycarbo= nates Alkyd-, Polyesters, Cellulose= ether, PVC (plasticized) Polyvinyl= acetate, PVC-copo= lymers Cellulose= ester Polyure= thane Acrylics, Polyester Phenol derivatives, Epoxies Polystyrenes, Arylsilicones, Aryl-alkyl= Silicone Co= polymers Polyamides, amines Nitrocellulose cellophan Cellophan, Alkylcellulose, PVA, PEO PAN, PVC, Polyvinyliden chlorid, POM Alkylsilicone, aliphatic hy= drocarbons, Polytetra= Fluorethylene, Thiokol sharp strong –1590, 1600 – 1580 and sharp strong All numbers have the meaning of wave numbers and are given in cm -1 yes no

Intensity, arbitrary units 1/d = 2 / n (1 /     n = number of minima between two maxima   and   wave length

cm cm cm cm cm -1 Polyamid epoxies, polycarbonate, alkyd resins, polyesters, cellulose-ether, PVC poly(vinyl acetate), PVC-copoly., cellulose ester, PU acryl polymers Phenol resins, epoxies, aryl polymers

cm -1 modified epoxides, polycarbonate, Alkyd resins, polyester, cellulose ester, cellulose ether, PVC (plast), PVAc, PVC-copolym., PU, acrylics cm modified epoxides, polycarbonate, Alkyd resins, polyester, cellulose ester, cellulose ether, PVC (plast) cm -1 Modified epoxies, polycarbonate polycarbonate

? cm cm cm -1 typical pattern of normal PC typical pattern of PU C-O-C-ether region Poly (ether urethane) ? cellulose ester or polyurethane ?

Infrared Spectroscopy:  760 nm….1mm near infrared “quartz-infrared” ~ 10,000…4,000 cm -1 NIR middle infrared “conventional” infrared ~4,000…250 cm -1 far infrared < 250 cm -1 use of quartz cuvettes and light pipes higher order absorptions (lower intensity) liquids can be measured in thicker layers

NIR Hydrogen-containing groups are dominant Information is often implicid, coupled vibrations Not suited for trace analysis Easy analysis of aqueous solutions Process-analysis Use of light-pipes even without cuvette (reflection) Easy analysis of powders using diffuse reflection Characterisation of fillers Determination of water contents in liquids and solids

4000 cm -1 …50 cm -1 fundamental vibrations 4000 cm -1 …400 cm -1 fundamental vibrations cm -1 …4000 cm -1 overtones & combinations scatteringabsorption monochromatic excitation sourcedispersed polychromatic radiation information from scattered radiationinformation from absorbed radiationhomonuclear functionalities changes in polarizability polar functionalities changes in dipol moment CH/OH/NH functionalities high structural selectivity low structural selectivity I raman ~ c Lambert-Beer-Law no sample preparation required no sample preparation required sample preparation required (except ATIR) sample volume µL sample thickness µm sample thickness up to cm-range sample volume µL sample thickness µm light-fiber optics >100 m light-fibre optics >100 m limited Raman MIR NIR

general pertubation mechanical, electric, electro-magnetic, chemical,… Electro-magnetic probe IR X-ray, UV-vis, NMR,…

Samples are exposed to external pertubations such as: temperature pressure stress Resolution (the large number of) overlapping NIR bands can be enhanced and MIR and NIR correlation spectra are very useful for peak assignement