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Failure analysis and material control


             Multifaceted Evaluation of Plastic Degradation                                                                           RoHS Directive Compliant Screening System for Phthalate Esters
             – Identifying Causes of Degradation and Understanding Effects of Degradation –                                           – Contributing to the More Rapid Inspection of Materials and Parts –



            Plastic properties can change or degrade not only due to heat, various organic solvents, or acidic or alkaline solutions, but also due to UV rays. In   The use of phthalate esters is currently restricted in toys, food packaging, and other applications and there are even plans to regulate them as a
            particular, if plastics are used outdoors (as automotive exterior parts, for example), they require UV resistance. Developing plastics resistant to UV   restricted substance under the Directive on the restriction of the use of certain hazardous substances in electrical and electronic equipment (RoHS
            degradation requires understanding the causes and effects of the degradation. A deeper understanding can be determined from multifaceted   Directive) in Europe. Even though transportation equipment is not governed by the RoHS Directive, due to the various industries involved in
            evaluations. As an example of multifaceted degradation evaluation, ABS resin pellets were irradiated with UV rays and then changes in the mechanical   reducing the use of the regulated substances, the automotive industry cannot ignore this trend.
            properties at the resin surface were evaluated. An FTIR system was used to measure an infrared spectrum to evaluate macromolecular structural changes   The Py-Screener phthalate ester screening system is able to significantly reduce the time and cost of analysis and is easy to operate even for
            and a dynamic ultra micro hardness tester was used to measure the hardness of the resin surface.                          first-time users.

              UV Irradiation Conditions                                                                                                 Screening System for Phthalate Esters
            UV irradiation: Ozone-free mercury-xenon lamp at less than 45 mW/cm  from 300 to 450 nm
                                                                         2
                                                                                                                                      System allows even first-time users to screen samples easily.
                                       Infrared Spectrum                           Hardness Measurement Conditions
                                       Measurement Conditions                      DUH-211S                                            Py-Screener
                                       IRTracer-100, QuestATR                      Test method: Test method: Loading-unloading test                  — Making the Complicated Simple
                                       Resolution: 4 cm -1                         Test force: 2.0 mN
                                       Accumulation: 40                            Test speed: 0.0975 mN/sec
                                       Apodization: Happ-Genzel                    Holding time: 2 sec
                                       Detector: DLATGS                            Indenter shape: 115-degree angle between diamond edges
                                                                                                                                                                                        Py-GC/MS-specific standard
                                                                                                                                                                                          phthalate ester sample
                                                                                                                                                                                      (jointly developed with SGS Japan)  Sampling toolkit
                                          C=C     =C-H
                                        Stretching vibratio  Out-of-plane
                                                 deformation
                                      C=O         vibration
                                   Stretching vibratio
                      O-H
                   Stretching vibratio
                                -C≡N
                             Stretching vibratio

                                                                                                                                                                                        Includes everything required for sample preparation




                             ABS Resin Infrared Spectrum                     ABS Resin Test Force vs. Depth Graph
                                                                                                                                              Sample preparation navigator                             Pass/fail results visible at a glance
            The results confirmed increased absorption due to O-H stretching vibration   The fact that penetration depth in respective sample surfaces
            or C=O stretching vibration when UV irradiation time was increased.   decreased as UV irradiation time increased confirms that the surfaces
            Decreased peak height was confirmed at 966 cm-1. That indicates   became harder.
            absorption due to =C-H out-of-plane deformation vibration of the
            trans-vinylene group contained in the butadiene. On the other hand, no
            significant changes were observed in the nitrile group -C≡N stretching
            vibration peak (near 2240 cm ) or the styrene C=C stretching vibration                                                            Measures samples easily by simply                        Navigator ensures reliable
                               -1
            peaks (near 1500 and 1450 cm  due to benzene ring angular vibration).                                                             entering sample information                              maintenance
                                -1
                                                                                                                                                                                                            <  Maintenance Navigator >
                                                                                                                                                                                                            Click a picture or description to view each item.
            These results suggest that ABS oxidation progresses from portions of the
            butadiene affected by UV rays.
            Both the infrared spectrum measurement and hardness measurement results show a tendency for properties to change as the UV irradiation time
            increases. It suggests that UV rays decrease the polymer’s original flexibility due to oxidative degradation of butadiene at the sample surface, which                                             Measures to take when  List of consumables and
                                                                                                                                                                                                                gas leak has occurred
                                                                                                                                                                                                                      replacement criteria
            makes it more prone to cracking.
                                                                                                                                                                 Dedicated software navigates necessary operations
               FT-IR Series                                      DUH Series
               · Thermal degradation can be efficiently identified using   · With the ability to measure hardness without measuring
                a thermal degradation library.                    indentation size, the series can evaluate the hardness of              · System does not require any organic solvents for sample preparation, reduces time and costs, and enables anyone to
               · Measurement data can be saved in a private library to   even polymer materials that are difficult to indent.             perform rapid screening easily.
                improve analysis capabilities by using previous   · Micro areas can be evaluated, such as on tiny samples or
                measurement results for identification.           surface layers, because hardness can be measured based
                                                                  on tiny indentation displacements.




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