Polymer and plastics analysis Quality control for polymer production 02 Metrohm ... • is the global market leader in titration • offers a complete portfolio for NIR and Raman analysis, in addition to all of the methods of ion analysis, titration, electrochemistry (e.g. voltammetry), and ion chromatography • is a Swiss company and manufactures exclusively in Switzerland • grants a 3-year instrument warranty and a 10-year warranty on chemical suppressors for anion chromatography • provides you with unparalleled application expertise • offers you more than 2000 applications free of charge • supports you with dependable on-site service worldwide • is not listed on the stock exchange, but is owned by a foundation • takes a sustainable approach to corporate management, putting the interests of customers and employees ahead of maximizing profit Content 1. Analytical techniques ............................................................................................................................ 5 03 1.1. Titration .........................................................................................................................................5 1.2. Karl Fischer titration .......................................................................................................................5 1.3. Ion chromatography ......................................................................................................................5 1.4. Combustion ion chromatography ...................................................................................................5 1.5. PVC-Thermomat method ................................................................................................................6 1.6. Near-Infrared Spectroscopy (NIRS) ..................................................................................................6 1.7. Raman spectroscopy ......................................................................................................................6 1.8. Voltammetry ..................................................................................................................................7 1.9. Electrochemistry .............................................................................................................................7 1.10. Multimethod process analysis ........................................................................................................7 2. Applications ........................................................................................................................................... 8 2.1. Quality control for raw materials ...................................................................................................8 2.1.1. Water determination ........................................................................................................9 2.1.2. Acid number, hydroxyl number, isocyanate determination ..............................................10 2.1.3. Impurities .......................................................................................................................12 2.1.4. Inhibitors: Online process analysis for raw material testing ..............................................13 2.1.5. Identification of raw materials using Raman spectroscopy .............................................13 2.2. Intermediates/reaction monitoring ...............................................................................................14 2.3. Quality control of the finished polymer ........................................................................................16 2.3.1. Water determination ......................................................................................................17 2.3.2. Halogens and sulfur in polymers .....................................................................................18 2.3.3. Heat resistance of PVC....................................................................................................20 2.3.4. Carboxyl determination .................................................................................................20 2.3.5. Spectroscopy for polymer testing ....................................................................................21 2.3.6. Residuals and impurities ..................................................................................................22 2.3.7. Electrically conductive polymers ......................................................................................25 04 Metrohm – customized polymer analysis for quality control of monomers, intermediate products, and finished polymers Polymers and plastics are a mainstay of modern life due various industries such as: paper, cosmetics, textile, or to their versatility and physical properties: they can be the building material in dustry. That makes the production formed into nearly any shape, with different degrees of process even more tricky. flexibility and other variable parameters. They have to meet supreme standards. Metrohm offers about 100 applications to help control the process of polymer production from Plastic components are widespread; they are used in air - monomer analysis through to final control planes and cars, packaging, medical devices and products, of finished products. Techniques range from electronics, and countless other products. Every year 370 tit ra tion and ion chromatography to spectroscopy million tons of plastic are produced worldwide. and voltammetry. Polymers also have a dark side: plastic waste is growing You can count on our know-how all the time. Plasticizers are harmful to human health. Metrohm offers you complete solutions for very spe cific Ha lo gens in plastic create corrosive and toxic hy dro gen-analytical issues. Your Metrohm contacts are profes sion- halides during combustion. Finally, there is the issue of als, who develop customized applications and provide microplastics infiltrating every corner of the environment. you with professional support in all matters con cerning poly mer analysis. We offer standardized methods and Polymer production is a demanding process in which high- secondary methods like Raman and NIR from one pro - purity raw materials undergo complex reactions and are vider. Our know-how, our experience, and our optimized turned into polymers, fibers, resins, rubbers, and gums. To methods help to increase throughput in a time-saving ensure that these products meet stringent spe cifications, and accurate way with lower cost. raw materials and processes must be mo nitored along the entire production chain. Analyses must be carried In this brochure, we present some selected applications out at every stage of production. It’s a complex process. used during polymer production. Do not hesitate to con - Also, some finished polymer products become feedtact our application specialists for help and more in for - stock for other goods and enter as raw materials in mation. Application Note (AN): Throughout the brochure the abbreviation «AN» stands for Application Note. You can find all the mentioned ANs in the Application Finder on our homepage www.metrohm.com/applications/ 1. Analytical techniques 1.1. Titration 05 Potentiometric titration is ideally suited for titrating func - valence points to be determined in low-conductivity media. tional groups in monomers, in particular monomeric Hundreds of titrations are applied in the polymer in dus-mono- and polyacids as well as polyols. These titrations try: from acid, hydroxyl, epoxy, carboxyl, and amine are mostly carried out in nonaqueous, nonpolar solutions number to chloride and isocyanate con tent. The most and are thus accompanied by very little potential change, common and readily auto ma ted analyses are hydroxyl leading to flat and erratic titration curves. Metrohm has and acid number as well as isocyanate content. Their overcome these drawbacks by developing instruments titrimetric determination is mainly regulated by ASTM and and sensors (e.g., Solvotrode easyClean) that allow equi - ISO standards. 1.2. Karl Fischer titration You can check the water content in gaseous and wa ter content at trace levels. As most polymers are not liquid monomers, in liquefied gases as well as in solid soluble, water determination is carried out using the Karl monomers in raw materials and even in finished plastics Fischer oven method, where residual moisture in the using Karl Fischer titration. Sensitive coulometric Karl plastic is evaporated and transfered to the titration cell Fischer titration is the ideal me thod for determining where it is subsequently titrated. 1.3. Ion chromatography Ion chromatography (IC) and combustion ion chroma- (AN-S-130), sodium, ammonium, and potassium in polye- tography have become efficient and precise methods thers (AN-C-059), and phosphate and sulfate in polymer to quantify compounds in the production of polymers, samples after inline dilution & inline dialysis (AN-S-230). from raw materials to finished consumer goods to components in effluent streams. New technologies such as In polyols, alkali metals represent some of the most ultrafiltration, automatic multipoint calibration and spe ­ critical impurities, because they are strong catalysts cialized cation analysis help monitor effluent streams for linear and branched reactions. Ion chromatography more easily and accurately than ever. This ensures that the after inline matrix elimination is a rapid and precise me-concentration of byproducts from polymer ma nufacturing thod for the simultaneous determination of sodium and processes meet regulated limits. Ion chromatography potassium. Additionally, IC is an effective technology for may also be used for other analyses, such as anions in final production testing and environmental moni to rper fluorocarbon material (AN­S­228), anions in PVC ing applications in the polymer industry. 1.4. Combustion ion chromatography Combustion Ion Chromatography (CIC) is well-suited for effl u ent monitoring. In this inline technique, the sample analyzing halogens, sulfur, and polychlorinated biphenyls undergoes pyrohydrolytic com bustion, where the com- (PCBs) in raw materials and finished products. Driven pounds of interest are converted into gaseous form and by recent technical advances in automation, CIC has then directly absorbed by a solution. This solution is then improved both its accuracy and ease of use. Standard IC ana lyzed via ion chromatography. is routinely used for the mea surement of various anions and cations in dis charge water for NPDES (National Combustion Ion Chromatography is an invaluable tool Poll u tant Discharge Elimination System) compliance, for the analysis of both raw materials and finished com and for quantification of amines in raw material and ponents in the polymer industry. 06 1.5. PVC-Thermomat method Metrohm’s 895 Professional PVC Thermomat determines mat and measuring the stability time – the time until the thermostability of polyvinyl chloride (PVC) and gaseous hydrogen chloride is released. The method is other chlorine-containing polymers by means of the compliant with national and international standards, and de hyd rochlorination test (DHC). This involves exposing it is par ticularly easy to perform. the samples to elevated temperatures in the PVC Thermo- 1.6. Near-Infrared Spectroscopy (NIRS) Metrohm laboratory analyzers for near-infrared (NIR) s copy are hydroxyl number, density, viscosity, melt spec troscopy enable users to perform routine analysis flow index, acid number, moisture content, diethylene (e.g., determination of hydroxyl number of polyols) glycol, and carboxylic end groups, to name but a few. quickly and reliably – without requiring sample prepa- As mea surements by Vis-NIR spectroscopy only take ra tion or additional reagents and yielding results in less a few seconds, it is the preferred method for real-time than a minute. These analyzers are capable of performing monitoring of chemical reactions. Looking beyond qualitative and quantitative analysis of a number of che mi cal parameters, Vis-NIR spectroscopy is also used physical and chemical parameters in one run. to determine blending homogeneity or particle size distri- bution. The combination of real-time analysis with supe - Vis-NIR spectroscopy is highly suited to analyze various rior accuracy and reliability makes Vis-NIR spectroscopy a polymers such as polyurethanes, PET, PVC, nylon etc. matchless technique for the polymer analysis. Common parameters determined by Vis-NIR spectro- 1.7. Raman spectroscopy With our handheld Raman analyzers, you can iden tify and unambiguously. Metrohm Instant Raman Analyzers common monomers comfortably and rapidly. Mono mers (Mira) combine ease of use with maximum safety and such as styrene, various alkyl methacrylates, divinyl ben-pro vide results within seconds. Raman can effectively zene, ethylene glycol, phenol, terephthalic acid, and urea dis tin guish materials such as ABS, PE, PS, PET, and can be analyzed within seconds. More over, additives or PMMA* in waste, irrespective of color, surface water, inhibitors such as benzoquinone can be identified quickly deformation, or dirt. *Acrylonitrile-butadiene-styrene copolymers (ABS), polyethylene (PE), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA) 1.8. Voltammetry 07 Voltammetry is a very sensitive technique for the analysis of raw material quality in polymer manufacturing. This of electrochemically active substances, such as inorganic tech nique combines a wide range of applications, short or organic ions and can also analyze neutral organic analysis times, and high precision and sensitivity with compounds. Voltammetry is very well suited to analysis comparatively low investment and operation costs. 1.9. Electrochemistry Our electrochemistry portfolio ranges from portable concept validation of new materials to characterization ins truments to modular systems for full flexibility and and quality control of materials and devices. One of the multi channel workstations allowing a number of expe-hottest materials currently being studied is graphene. ri ments to be performed simultaneously. Electro chemical Graphene is apt for electrochemical research because it measurements are used for the characterization of has special electrical, optical, and mechanical properties elec trochemically active materials and interfaces which and is a two-dimensional covalently linked poly mer. It is in volve electron or charge transfer (e.g., conductive used extensively as electrode material and substrates in poly mers). Electrochemical measurements are all based many electrochemistry application fields. Specially mo on a highly accurate control and measurements of vol - dified, ready­to­use graphene screen­printed elec trodes tage, current, electrical charge, or impedance and are (SPE) are available from Metrohm DropSens. Essen tial rea lized with specially designed potentiostats/ga lva- measurement techniques in the NOVA 2 software, used nostats. Research encompasses the progressive deve- with any of the potentiostats/galvanostats provided by lop ment trajectory of the compounds from theory and Metrohm Autolab, allow in­depth research in this field. 1.10. Multimethod process analysis Our inline, online, and atline process analyzers allow wide range of analytes and in various configurations – you to monitor different parameters in real time, con - rang ing from single-parameter systems to multiparameter ti nuously, and fully automatically. They can thus be ana lyzers performing titration, ion chromatography, vol - seamlessly integrated into almost any production pro - tammetry, photometry as well as direct measurements or cess. Our industrial process analyzers are available for a measurements with ion-selective electrodes. 2. Applications 08 2.1. Quality control for raw materials A final product can only be as good as the ma te- Metrohm offers a range of instruments and methods rials used to make it. Regular and systematic analyses that meet any requirements in raw materials inspection: of incoming starting material assure certain identity from easy-to-use out-of-the-box systems to customized and quality attributes of the final product before the setups tailored to your application challenge. In addition, production process has begun. Given the importance of Metrohm gives you access to an extensive pool of raw material quality, analyses must be specific, reliable, industry­specific application know­how free of charge. and precise – and given the importance of economic aspects such as time to market, analyses must be efficient and time-saving as well. Parameter Standard Matrix Method Acid number ASTM D4662 Polyol (in PU production) Titration Acidity ASTM D5629 Low-acidity aromatic isocyanates and PU prepolymers Titration ASTM D6099 Moderate- to high-acidity aromatic isocyanates ISO 14898 Aromatic isocyanates in PU production Free acidity EN ISO 1061 Unplasticized cellulose acetate Titration Alkalinity/basicity ASTM D4662 Polyol (in PU production) Titration ASTM D6979 ISO 14899 ASTM D6437 Total aldehydes ASTM D7704 Styrene monomer Titration Total chlorine ASTM D4661 Isocyanates Titration Hydrolyzable chlorine ASTM D4663 Isocyanates Titration Degree of unsaturation ISO 17710 Polyol (in PU production) Titration ASTM D4671 Hydroxyl groups ASTM E1899 Polyol (in PU production) Titration Hydroxyl number ASTM D4274 Polyol (in PU production) Titration ISO 14900 ASTM D6342 NIRS ISO 15063 NIRS Permanganate ISO 8660 Caprolactam Photometry absorption number Water ASTM D5460 Rubber additives KFT ASTM D4672 Polyol (in PU production) KFT ISO 14897 Polyol (in PU production) 09 2.1.1. Water determination Contaminants in raw materials like water can significantly hamper the production process. Water can be quantified using Karl Fischer titration regardless of the physical state of the monomer. You can check the water content in gase ous and liquid monomers as well as in liquefied gases using Karl Fischer titration. Additionally you can analyze solid samples with the KF oven method. 874 USB Oven Sample Processor, 851 Titrando (coulometric cell) and titration software tiamo. Water determination in liquid monomers APPLICATION NOTES: • Water in melamine AN-K-034 • Water in beta-caprolactam AN-K-035 Butadiene gas – water determination 10 Water determination in gaseous monomers APPLICATION NOTES: • Water in propene AN-K-066 • Water in butadiene AN-K-060 855 Robotic Titrosampler for acid/base titration 2.1.2. Acid number, hydroxyl number, isocyanate determination When acrylic acid dimerizes, the acid groups of two mo - The titration takes place in a nonaqueous solution. The nomers react with one another. The number of free acid low conductivity of the medium makes it harder to de ter - func tions per gram of material thus reflects the dimer mine the endpoint po tentiometrically, but suitable sen - content. The acid number – i.e., the amount of potassium sors such as the Metrohm Solvotrode easyClean enable hydroxide (KOH) in milligrams which is required to neu - precise determinations nonetheless. The analysis can be tralize one gram of sample – is therefore determined as a fully automated. quality indicator. This is done by titration (figure below). Acid number as per ASTM D4662 and ISO 2114. Determination of acid number APPLICATION NOTES: • Acid value, hydroxyl value, and isocyanates in raw materials for plastics by titration AB-200 11 • Partial acid number in unsaturated polyester resin in accordance with EN ISO 2114 AN-T-164 • Total acid number in unsaturated polyester resin according to EN ISO 2114 AN-T-165 • Acid number in acrylic acid AN-T-160 Hydroxyl number as per ASTM E1899, EN ISO 4629-2, and EN ISO 2554 APPLICATION NOTES: • Fully automated potentiometric determination of the hydroxyl number (HN) according to ASTM E1899 and EN ISO 4629-2 AB-322 • Hydroxyl number in polyols and oxo alcohols according ASTM E1899 AN-T-178 • Hydroxyl number in polyols and oxo alcohols according to EN ISO 4629-2 AN-T-177 Isocyanates as per EN ISO 11909, EN ISO 14896, and EN ISO 2554 APPLICATION NOTES: • Isocyanate in unsaturated polyester resin and polyurethane resin in accordance with ISO 14896 AN-T-167 • Acid value, hydroxyl value, and isocyanates in raw material for plastics by titration AB-200 Isocyanate determination Feedstock analysis/parameter check in real time by spectroscopy APPLIC ATION NOTES: • Hydroxyl in polyols AN-NIR-006 • Isocyanate content using Vis-NIR spectroscopy AN-NIR-068 • Hydroxyl number in liquid polyols using Vis-NIR spectroscopy AN-NIR-035 • Simultaneous determination of multiple quality parameters of polyols using Vis-NIRS AN-NIR-065 12 2.1.3. Impurities Sodium and potassium in polyol by IC There are also contaminants in raw materials, like sodium and potassium, that can significantly impair the production process. APPLICATION NOTE: • Sodium and potassium in polyol using IC following inline matrix elimination AN-C-157 460 462 464 466 sodium; 11.8 mg/kg 468 470 472 Conductivity [µS/cm] 474 potassium; 18.0 mg/kg 476 478 480 0 1 2 3 4 5 6 7 8 9 10 Time [min] Sodium and potassium determination 4-CBA in polyterephthalic acid and iron in ethylene glycol APPLICATION NOTES: • Polarographic determination of 4-carboxybenzaldehyde in terephthalic acid by polarography AB-190 • 4-Carboxybenzaldehyde in polytherephthalic acid AN-V-062 • Iron (total) in ethylene glycol with 2,3 dihydroxynaphthalene AN-V-123 884 Professional VA semiautomated, single determination. 2.1.4. Inhibitors: Online process analysis for raw material testing 13 TBC in styrene, butadiene, or vinylacetate APPLICATION NOTE: • 4-tert-butylcatechol in styrene in accordance with ASTM D4590 AN-PAN-1027 Caprolactam purity monitoring in accordance with ISO 8660 APPLICATION NOTE: • Permanganate absorption number AN-PAN-1011 H N O O H N n n nylon 6 caprolactam Carbolactam determination 2.1.5. Identification of raw materials using Raman spectroscopy How does it work? The instrument illuminates a sample providing an unambiguous fingerprint for each molecule. with laser light and then detects scattered photons. The figure below shows the Raman spectra of some Elastically scattered photons have the same energy before common monomers. and after interacting with the sample, so they do not provide any information about the identity of the sample. Peak positions in the Raman spectra provide information They are of no value for determination. In the case of in - about the molecular structure of a sample molecule. elastically scattered photons, interactions between light The difference between the frequency of incident and and the sample result in changes in the frequency of scattered photons, the Raman shift, corresponds to photons. This change in frequency provides information characteristic bond vibrations, which can be used to about the sample: these shifts are characteristic of the identify a molecule. Chemometric analysis and library molecular structure of the sample. The resulting pattern match ing allow for assignment of each spectrum to a – the Raman spectrum – of each substance is unique, known compound. 16000 C-O C=C Ethylene glycol (800-900) Ethyl methacrylate 14000 Hydroquinone Terephthalic acid CC=O bend Styrene 12000 CH /CH 2 3 C=O 10000 In-plane ring vib 8000 Intensity Ring vib 6000 4000 2000 0 400 600 800 1000 1200 1400 1600 1800 2000 2200 Wavenumber [cm-1] Raman spectra of some common monomers. 14 Monomers determination APPLICATION NOTE: • Identification of monomers with Raman AN-RS-008 This Application demonstrates the convenient identificae ne glycol, phenol, tere phthalic acid, and urea can be tion of conventional monomers within seconds using distinguished. Additives or inhibitors such as benzo quin-the handheld Mira analyzer. Monomers such as sty- one can be identified quickly and un ambi guo usly. re ne, various alkyl methacrylates, divinylbenzene, ethyl- 2.2. Intermediates/reaction monitoring With NIRSystems, you can benefit from technologies help you track what is going on in your reactors. These that provide tailored solutions that make your industrial techniques yield results in seconds, do not require any processes safer, more eco-friendly, and more effective. chemical reagents, and are nondestructive. With these systems, you no longer have to worry about sampling or Spectroscopic methods are predestined for polymerization sample preparation. process monitoring. Available as benchtop, as well as inline monitoring systems, Metrohm NIRSystems analyzers Process optimization through real-time analyses with spectroscopy APPLICATION NOTES: • Analysis of polymer using near-infrared spectroscopy AB-414 • Inline monitoring of free isocyanate content in polyurethane AN-PAN-1041 • Near-infrared analysis of polyols: process monitoring in rough environments AN-NIR-007 15 Reaction monitoring using online and inline process analyzers More than four million tons of viscose fibers are produced Online determination of acid and zinc concentrations is worldwide each year for the textile industry. Viscose essential for controlled production. It can be carried out is produced from cellulose, a natural polymer which is simultaneously with the ADI 2045TI Process Analyzer ob tained from pulp. The fibers are produced using the from Metrohm Process Analytics. The ADI 2045TI Ex proof wet-spinning method in a bath containing sulfuric acid, Process Analyzer is the preferred solution for hazardous sodium sulfate, and zinc sulfate. Each of these substances environments where explosion proof protection is a must. has a different task in the production process. Altering Our NIRS XDS Process Analyzer provides up to nine inline their concentrations changes the properties of the fibers, measuring channels helping to monitor several process enabling different types of viscose fibers to be produced. streams simultaneously without chemical reagents. Sulfuric acid and zinc sulfate in viscose/rayon production APPLICATION NOTE: • Sulfuric acid and zinc sulfate AN-PAN-1010 Determining sulfuric acid traces in acetone and phenol APPLICATION NOTE: • Sulfuric acid in acetone and phenol AN-PAN-1008 Analysis of dyeing plastics during manufacturing APPLICATION NOTE: • Identification of various polymer master batches with Raman Spectroscopy AN-RS-007 Solvent monitoring/recovery In many chemical processes, solvents can be a significant on waste disposal, and reduce liability associated with cost incurred in producing the final polymer product. A storing excess on-site. Ensuring that recovered solvents way to optimize production costs for polymers is to look are sufficiently pure for their intended reuse or are safe at improving solvent recovery processes. Solvent recovery for disposal is made simple with analytical techniques that systems help reduce consumption of pure solvent, save determine halogen, sulfur, water and methanol levels. APPLICATION NOTES: • Monitoring the purity of recovered solvents with NIRS, AN-NIR-021 • Halogens and sulfur in residual solvent using Combustion IC, AN-CIC-002 16 2.3. Quality control of the finished polymer High-performance polymers are used in virtually any in - duction steps. To ensure that the polymers conform to dustry and are essential components of many consumer specifications, quality control of the finished products is a pro ducts. The carefully designed properties of every poly - key aspect in the production chain. mer are achieved through very precise and complex pro - Standards for quality control in polymer and plastics production Parameter Standard Matrix Method pH value EN ISO 1264 Vinyl chloride resins pH value ISO 8975 Plastic, phenolic resins Electrical conductivity ISO 9944 Plastics, phenolic resins Conductivity (Total) Acid number ASTM D1386 Synthetic and natural waxes Titration EN ISO 2114 Polyester resins, paints and varnishes (binders) Amine groups ISO 9702 Amine epoxide hardeners Titration Epoxy contents ASTM D1652 Epoxy resins Titration Hydrolyzable chloride ASTM D1726 (Liquid) Epoxy resins Titration Epoxide equivalent ISO 3001 Epoxide compounds Titration Free phenols ISO 119 Phenol-formaldehyde mouldings Titration Hydroxyl groups ASTM E1899 Polyol (in PU production) Titration Hydroxyl value EN ISO 2554 Unsaturated polyester resins Titration EN ISO 4629-2 Binders for paints and varnishes Vinyl acetate content ISO 8985 Ethylene-vinyl acetate copolymers (EVA) and Titration further thermoplastics (VA/AA, PVA, PVCA) Formaldehyde content ISO 11402 Phenolic and amino resins Titration Water ASTM D6869 Plastics KFT ISO 15512 SH/T 1770 Polyethylene (PE) Thermostability ISO 182-3 Vinyl chloride homo-/copolymers Oxidation stability Bromine EN IEC 62321-3-2 Halogen-free cable and wires Combustion Ion Chromatography Carboxyl end groups ASTM D7409 Polyamides/Polyester Titration Epoxy contents ASTM D1652 Epoxy resins Titration Rubber ISO 19242 Determination of total sulfur content IC 17 2.3.1. Water determination Excessive amounts of water in finished products may soluble, the analysis is carried out using the Karl Fischer adversely affect their properties. Sensitive coulometric oven method: the residual moisture in the plastic is Karl Fischer titration is the ideal method for deter min-heated in order to evaporate it prior to titration. ing low water content. As most polymers are not water Water content in different plastic types Polymer type ABS1 PA2 PPA3 PC4 PET5 Standard ater -W® Sample d KF-Oven, 220...230°C, 5.57 ± 0.05% HYDRANAL Standar Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sample 6 Sample 7 Sample 8 Sample 9 Oven temperature 230°C 230°C 150°C 150°C 150°C 150°C 230°C 230°C 230°C 230 °C 5.63 1 1371.0 1078.2 1059.7 907.8 1006.3 695.7 1180.4 2196.2 1661.2 1 & 2 5.56 5.52 2 1382.9 1103.0 1057.0 925.0 1028.4 755.9 1167.4 2146.2 1644.3 3 & 4 5.54 5.59 3 1384.3 1116.2 1078.4 940.8 1042.6 741.2 1186.0 2144.1 1632.5 5 & 6 5.54 5.48 4 1398.1 1183.4 1120.7 993.9 1049.7 773.4 1185.9 2176.1 1635.2 7 & 8 5.50 5.58 5 1401.1 1199.2 1114.2 972.0 1065.7 786.6 1174.1 2203.8 1648.5 9 & 10 5.48 Mean value [µg/g] 1387.5 1136.0 1086.0 947.9 1038.5 750.6 1178.8 2173.3 1644.3 5.54% Uncertaintya [µg/g] 15.2 65.4 37.0 43.4 27.9 43.7 10 34.3 14.2 0.034% 1ABS = acrylonitrile-butadiene-styrene-copolymer, 2PA = polyamide, 3PPA = poly(phthalamide), 4PC = polycarbonate, 5PET: poly(ethylene terephthalate) aUncertainty = student t-factor × standard deviation × (number of single determinations)0.5 18 Determination of water in plastic APPLICATION NOTES: • Water content of soft contact lenses AN-NIR-020 • Parallel determination of water content by KF and potentiometric acid-base titration AN-K-068 • Water in plastic pellets – Interference-free determination based on ASTM D6869 AN-K-049 • Water in expandable polystyrene – Oven system with closed sample vials simplifies analysis AN-K-017 2.3.2. Halogens and sulfur in polymers The halogens present in polymer waste can potentially and consumer products and materials. Regulations af fec-enter into the environment as carcinogenic compounds. ting composition, waste, and energy use in the production This has led to efforts to reduce halogen con tent in com - of polymer products have already been adopted in many ponents used in the manufacturing of various electronic countries. Combustion IC drastically reduces the need for front- direct analysis by IC. This is a straightforward, fully au - end sample preparation as the sample is pyrolyzed in an to mated process which both reduces analysis time and oxidizing environment. The resulting gaseous hydrogen yields reproducible results. halide is trapped in an absorption solution followed by DIN EN 62321-3-2 stipulates CIC for determining total bromine in electric and electronic products APPLICATION NOTE: • Chlorine, bromine, and sulfur in low-density polyethylene applying Combustion Ion Chromatography AN-S-290 19 Compliance with Restriction of Hazardous Substances Polyisobutene (PIB) is an important raw material for the directive (RoHS) requires that the halogen content in manufacturing of fuel and lubricant additives to control various organic materials is drastically reduced. This has corrosion. Monitoring of halogens is important during the created a great demand for halogen-free polymers for manufacturing of additives for corrosion control. PIBs are various manufacturing operations. (AN-CIC-010). also used in the manufacturing of synthetic rubber and as a base material for the manufacture of chewing gum. (AN-CIC-008). Determination of the following parameters with CIC: Parameter Matrix Application Note chlorine, bromine, sulfur low-density polyethylene AN-CIC-003 halogens, sulfur latex gloves AN-CIC-004 chlorine, bromine, sulfur polyethylene pellets AN-CIC-006 fluorine polyisobutene AN-CIC-008 halogens polymers AN-CIC-010 bromide polystyrene AN-CIC-022 halogen, sulfur chlorinated and brominated halobutyl rubber AN-CIC-021 chlorine, bromine, sulfur low-density polyethylene AN-S-290 chlorine, bromine, sulfate electronic material AN-CIC-015 Important norms and standards: • Total bromine polymers by Combustion ion chromatography as per IEC 62321-3-2 • Electronic base material tested for halogen­free definition applying CIC as per IEC 61249-2-21 • Rubber total sulfur content with CIC as per ISO 19242 763 PVC Thermomat with PC. 20 2.3.3. Heat resistance of PVC Dehydrochlorination test as per ISO 182-3: Measuring the thermo - stability of polymers APPLICATION NOTES: • Thermostability of PVC and other chlorine-containing polymers AB-205 This Application Bulletin describes the determination time. The test is suitable for monitoring the manu fac-of the thermostability of PVC in accordance with ISO turing and processing of PVC products during the injection 182 Part 3 using the dehydrochlorination method with molding process as well as during final inspection. The the 895 Professional PVC Thermomat. This instrument comparison of PVC products and testing the effectiveness enables the fully automatic determination of the stabi lity of heat stabilizers are other applications of this method. • Thermostability of pure, blended, and processed PVC AN-R-008 • Thermostability of PVC AN-R-016 2.3.4. Carboxyl determination APPLICATION NOTE: • Carboxyl end groups in polymers – Photometric determination based on ASTM D7409 AN-T-087 DS2500, Multisampler with polymer sample 2.3.5. Spectroscopy for polymer testing 21 Checking additives in finished plastics APPLICATION NOTES: • Determination of additives in polymer pellets by near-infrared AN-NIR-004 • Determination of coatings on nylon fibers by near­infrared spectroscopy AN-NIR-005 • Diethylene glycol, isophthalic acid, intrinsic viscosity, and acid number in PET granulate by NIRS AN-NIR-023 • Textile analysis using near-infrared spectroscopy AB-413 • Determination of amine number and solid content of dipping paint AN-NIR-030 • Analysis of polymer granulate using near-infrared spectroscopy AN-NIR-034 • Quality control of polyamide using Vis-NIR spectroscopy (Nylon) AN-NIR-060 • Simultaneous determination of multiple quality parameters in epoxy resins using Vis-NIR spectroscopy AN-NIR-067 Checking copolymer levels in finished plastics APPLICATION NOTE: • Analysis of copolymer levels in polymer pellets by near-infrared spectroscopy AN-NIR-003 This application describes the determination of copolymer requires no sample preparation. The second derivative levels in polyethylene (PE) and polyvinylacetate (PVA) spectra are analyzed by the linear least-squares re gres - pellets using NIRS. The determination of the composition sion method. of the polymer blends takes less than 30 seconds and Checking copolymer levels in finished plastics by spectroscopy. 22 Fast identification of postconsumer plastic with material type analysis for recycling APPLICATION NOTE: • Identifying Polymers with Raman Spectroscopy AN-RS-001 This Application Note describes the Raman spectroscopy base has been created. Measurements with the Raman identification of polymers such as ABS, PE, PS, PET and spectrometer Mira require no sample preparation and PMMA* in various dyes. Rapid and non-destructive de - provide im mediate and unambiguous results. termination takes place after a suitable spectrum data- * Acrylonitrile-butadiene-styrene copolymers (ABS), polyethylene (PE), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA) 2.3.6. Residuals and impurities IC has proven to be an effective technology for final pro duct testing and environmental monitoring ap pl ications in the polymer industry. APPLICATION NOTES: • Phosphate and phosphite in poly(vinylphosphonic acid) using dialysis for sample preparation AN-S-063 This AN describes the determination of phosphate and matography with conductivity detection after chemical phosphite in poly(phosphonic acid) using anion chro - suppression and dialysis for sample preparation. • Fluoride, glycolate, chloride, and oxalate in a latex dispersion AN-S-122 • Six anions in PVC AN-S-130 • Anions in perfluorocarbon AN-S-228 23 More IC applications for determination of impurities Parameter Matrix melamine acetic acid borate resin powder cations finely ground polymer zinc finely ground polymer silicate finely ground polymer fluoride, phosphate, sulfate concrete, cement, plasticizer phosphate and sulfate polymers sodium acrylate resin cations PVC anions PVC formate and acrylic acid polymer sodium, potassium epoxy resin chloride, bromide, nitrate epoxy resin phosphate, phosphite 30% polyvinylphosphonic acid 24 Styrene in finished polystyrene / example food packaging and toxic styrene APPLICATION NOTES: • Polarographic determination of styrene in polystyrene and copolymers AB-136 This Application Bulletin describes a simple polarogra phic Before the determination, styrene is converted to the method to determine monomeric styrene in poly mers. elec trochemically active pseudonitrosite using sodium The limit of determination lies at 5 mg/L. nitrite. • Free styrene in polystyrene and mixed polymers AN-V-064 styrene -80 -70 -60 -50 I [nA] -40 -30 -20 -50 -100 -150 -200 -250 -300 -350 U [mV] Styrene determination Heavy metals in polymers APPLICATION NOTES: • Titanium in polyethylene terephthalate (PET) AN-V-113 • Cobalt in polyethylene terephthalate (PET) AN-V-114 • Antimony in polyethylene terephthalate (PET) AN-V-115 884 Professional VA 25 2.3.7. Electrically conductive polymers In general, synthetic polymers are isolators. However, if Various electrochemical techniques can be applied to they possess an extensive π electron system, they can re search in the field of conducting polymers: Cyclic vol ­ (semi)con duct electricity. The most common conducting tam metry (CV), Chronoamperometry (CA) and Chrono - polymer (CP) materials are polyaniline, polypyrrole, as well coulometry (CC). These can be used in hyphe nation as po ly thiophene and its derivatives. By incorporating with Quartz Crystal Microbalance (QCM) and are the doping ions or substituents, metal-like conductivities and most common techniques used to monitor formation other exceptional properties are obtained. These materials and deposition of polymers as well as the kinetics of are used from organic light-emitting diodes (OLEDs) to charge transfer mechanisms. Electrochemical Impedance poly mer solar cells or conducting polymer-based super - Spectroscopy (EIS) is the most powerful electrochemical ca pacitor devices and electrodes. To investigate the technique used for in-depth characterization of the elec trochemical properties of conducting polymers or charge transfer mechanisms and interfacial processes of polymer electrolytes dur ing electrodeposition, in situ which may take place between the conducting polymer measurements such as electrochemical impedance spec-and the environment (electrolyte). troscopy (EIS) and cyclic voltammetry are required. In these leading-edge tech nologies, researchers all over the Other non-electrochemical techniques can also be used world rely on Metrohm Autolab instruments. simultaneously with electrochemistry to further under - stand the nature of charge transport within ma terials The synthesis, characterization, and use of conductive po - and the relationship between the structure of a material ly mers play an important role within the polymer in dustry and its chemical and electrochemical properties. Some because of the versatile applicability of these materials in examples of analytical techniques which can be combined different areas such as: energy storage and generation with electrochemistry: UV-VIS spectroscopy, microscopy devices, electrochromic displays, sensors, electrocatalysis, (optical, AFM, STM, SECM), and ellipsometry. corrosion protection, and coatings. Metrohm Autolab offers a full range of electrochemical instruments and accessories to meet the needs of re - searchers working in the field of conductive polymers. Parameter Standard Matrix 26 DC Resistance ASTM D4496 Moderately Conductive Materials Volume Resistivity ASTM D991 rubbers used in electrically conductive and antistatic products Standard Test Methods for DC Resistance or Conductance DC Resistance ASTM D257 of Insulating Materials Engineering Dielectrics Volume IIB Electrical Properties of Electrical Properties ASTM STP926 Solid Insulating Materials: Measurement Techniques Rubber, vulcanized -- Antistatic and conductive products -- Resistance ISO 2878 Determination of electrical resistance Autolab PGSTAT302N with an EQCM module with laptop and NOVA 2. Verify materials at the touch of a screen! Mira P is the new handheld Raman analy- zer for the pharmaceutical industry. Fast and accurate, Mira provides guided work- flows and supports FDA 21 CFR compliance with audit trails, report generation, and secure electronic records. • Inspection of incoming goods • Formulation verification • Process monitoring www.metrohm.com www.metrohm.com G, CH-9100 Herisau ohm A witzerland by Metr , printed in S SW Subject to modifications Layout by Ecknauer+Schoch A 8.000.5287EN – 2019-04