8 research outputs found

    The future of isosorbide as a fundamental constituent for polycarbonates and polyurethanes

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    Isosorbide is a biobased compound which could become in the near future an advantageous competitor of petroleum-derived components in the synthesis of polymers of different nature. When the reactivity of isosorbide is not enough, it can be successfully transformed into secondary building blocks, such as isosorbide bis(methyl carbonate), which provides extra functionalities for polymerization reactions with diols or diamines. The present review summarizes the possibilities for isosorbide as a green raw material to be used in the synthesis of polycarbonates and polyurethanes to obtain products of similar or enhanced properties to the commercial equivalents.This paper is a part of the research carried out within the VIPRISCAR project which has received funding from the Bio-Based Industries Joint Undertaking (JU) under the European Union’s Horizon 2020 research and innovation programme under grant agreement No 790440. The JU receives support from the European Union’s Horizon 2020 research and innovation programme and the Bio-Based Industries Consortium

    Sampling strategies for the analysis of reactive low-molecular weight compounds in air

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    Within this thesis, new sampling and analysis strategies for the determination of airborne workplace contaminants have been developed. Special focus has been directed towards the development of air sampling methods that involve diffusive sampling. In an introductory overview, the current state-of-the-art of sampling and analysis of airborne isocyanates is reviewed. The most important\ud derivatization reagents are introduced, and their application for air analysis with special emphasis on sampling techniques and detection methods is presented

    Validation of a diffusive sampling method for airborne low-molecular isocyanates using 4-nitro-7-piperazinobenzo-2-oxa-1,3-diazole-impregnated filters and liquid chromatography–tandem mass spectrometry

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    A diffusive sampling method for the determination of low-molecular isocyanates as their 4-nitro-7-piperazinobenzo-2-oxa-1,3-diazole (NBDPZ) derivatives using tandem mass spectrometry (MS/MS) after atmospheric pressure chemical ionisation (APCI) is presented. Isocyanic acid (ICA), methyl isocyanate (MIC), ethyl isocyanate (EIC) and phenyl isocyanate (PhIC) are collected on NBDPZ-impregnated polystyrene divinyl benzene (SDB) filter tapes. The method was validated for MIC, EIC and PhIC for concentrations between 0.5 and 50 ppb at relative humidity (RH) conditions from 10 up to 90%. Validation was carried out by active sampling using 1-(2-methoxyphenyl)piperazine (2-MP) as derivatising agent. Sampling periods applied were between 15 min and more than 8 h. The sampling rates were determined to be 21.0 mL/min for MIC with a relative standard deviation (RSD) of 9.0% for 184 samplers, 15.6 mL/min for EIC (RSD 11.6%; N = 154) and 11.5 mL/min for PhIC (RSD 8.4%; N = 87). The limits of quantification were 1.4 ppb for MIC and 1.3 ppb for EIC and PhIC applying 15 min sampling periods. Owing to high background signals, isocyanic acid could only be determined when it was present in concentrations in the high ppb rang

    Life cycle assessment of bio-based, waterborne PU adhesives for fast industrial bonding processes

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    Aqueous PU dispersion adhesives based on high molecular weight, semi-crystalline polyurethane polymers have long demonstrated their outstanding performance and are a well-established bonding technology in several industrial applications. Due to their thermal activation properties and sharp melting area, these adhesives allow for efficient bonding processes with short bond strength build-up times. State-of-the-art is the use of polyester building blocks from fossil raw material resources to synthesize the base polymers. As the use of biobased raw materials and sustainability is increasingly a factor in public and customer perception, it is also becoming increasingly important in industrial processes and company strategies. For these reasons, a consortium of industrial and research partners is working to develop bio-based solutions for PU dispersion adhesives using significant amounts (> 50 %) of renewable raw materials. Target applications include the automobile, furniture and shoe industries. In order to investigate the environmental performance of the new biobased adhesive, a life cycle assessment is carried out. First results indicate that the carbon footprint of the adhesive can be reduced by more than 25% when comparing the biobased adhesive to fossil-based PU dispersions. This project is supported by the “Fachagentur Nachwachsende Rohstoffe” (FNR) on behalf of the German Federal Ministry of Food and Agriculture (BMEL) by decision of the German Bundestag

    Passive Sampling of Airborne Peroxyacetic Acid\ud

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    The first passive sampling device for the determination of airborne peroxyacetic acid (PAA) is presented. 2-([3-{2-[4-Amino-2-(methylsulfanyl)phenyl]-1-diazenyl}phenyl]sulfonyl)-1-ethanol (ADS) is used to impregnate glass fiber filters, and the reagent is oxidized by PAA to the corresponding sulfoxide ADSO. After elution of the filters, ADS and ADSO are separated by reversed-phase HPLC and detected by UV/visible absorbance. Limit of detection is 30 ppb, limit of quantification is 90 ppb (for 30 min sampling), and the linear range comprises 2 orders of magnitude. Thorough investigations were carried out with respect to the selectivity of the method toward hydrogen peroxide, and air samples were analyzed successfully after disinfection of a laboratory area. \u

    Passive Sampling of Airborne Peroxyacetic Acid

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    Determination of airborne isocyanates

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