Gabriela Díaz Gorbea, Liyang Shen, Kendra Flanigan, Christopher J. Ellison* and Frank S. Bates*,
{"title":"用聚丁二烯衍生嵌段共聚物增强消费后回收聚烯烃的韧性","authors":"Gabriela Díaz Gorbea, Liyang Shen, Kendra Flanigan, Christopher J. Ellison* and Frank S. Bates*, ","doi":"10.1021/acsapm.4c0227010.1021/acsapm.4c02270","DOIUrl":null,"url":null,"abstract":"<p >There is a rapidly expanding need for economically viable approaches for ameliorating the wasteful disposal of post-consumer plastics in landfills and the leakage of these materials into the environment. Here, we assess the efficacy of poly(ethylene)-<i>block</i>-poly(ethylene-<i>ran</i>-ethyl ethylene)-<i>block</i>-poly(ethylene) (EXE) triblock copolymers as compatibilizers in post-consumer recycled poly(ethylene) (rPE) and <i>isotactic</i> polypropylene (rPP) containing ca. 10–15% PP and PE impurities, respectively. E<sub>67</sub>X<sub>138</sub>E<sub>67</sub> was prepared by anionic polymerization of butadiene followed by catalytic hydrogenation, where the subscripts indicate block molecular weight in kg/mol. This triblock copolymer was mixed with rPE and rPP, along with blends formed from virgin PE and PP, and the recycled and blended materials were characterized by differential scanning calorimetry (DSC), atomic force microscopy (AFM), and tensile testing. The presence of phase-separated impurities in the recycled plastics was confirmed by DSC and AFM, and shown to contribute to inferior mechanical properties, <i>e.g.</i>, strain at break, ε<sub>b</sub> < 20% for melt-molded specimens cooled at 38 °C/min, referred to as fast cooling. Addition of 1 wt % of E<sub>67</sub>X<sub>138</sub>E<sub>67</sub> to rPE and rPP led to improvements in ductility, dependent on the rate of cooling of melt-molded specimens. Fast cooling produced marginal gains in ductility, ε<sub>b</sub> ≈ 90 and 30% in rPE and rPP, respectively. However, industrially relevant very fast cooling (380 °C/min) dramatically improved the ductility, where ε<sub>b</sub> ≥ 500% for both recycled plastics. Similar results were obtained with virgin PE/PP blends containing 1 wt % E<sub>67</sub>X<sub>138</sub>E<sub>67</sub>. These findings are compared with the results described in a previous report, where 1 wt % E<sub>65</sub>X<sub>88</sub>E<sub>65</sub> was added to virgin PE/PP blends, indicating that the X block molecular weight plays an important role in the efficacy of compatibilization.</p>","PeriodicalId":7,"journal":{"name":"ACS Applied Polymer Materials","volume":null,"pages":null},"PeriodicalIF":4.4000,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Enhancing Toughness of Post-Consumer Recycled Polyolefins with Polybutadiene-Derived Block Copolymers\",\"authors\":\"Gabriela Díaz Gorbea, Liyang Shen, Kendra Flanigan, Christopher J. Ellison* and Frank S. Bates*, \",\"doi\":\"10.1021/acsapm.4c0227010.1021/acsapm.4c02270\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<p >There is a rapidly expanding need for economically viable approaches for ameliorating the wasteful disposal of post-consumer plastics in landfills and the leakage of these materials into the environment. Here, we assess the efficacy of poly(ethylene)-<i>block</i>-poly(ethylene-<i>ran</i>-ethyl ethylene)-<i>block</i>-poly(ethylene) (EXE) triblock copolymers as compatibilizers in post-consumer recycled poly(ethylene) (rPE) and <i>isotactic</i> polypropylene (rPP) containing ca. 10–15% PP and PE impurities, respectively. E<sub>67</sub>X<sub>138</sub>E<sub>67</sub> was prepared by anionic polymerization of butadiene followed by catalytic hydrogenation, where the subscripts indicate block molecular weight in kg/mol. This triblock copolymer was mixed with rPE and rPP, along with blends formed from virgin PE and PP, and the recycled and blended materials were characterized by differential scanning calorimetry (DSC), atomic force microscopy (AFM), and tensile testing. The presence of phase-separated impurities in the recycled plastics was confirmed by DSC and AFM, and shown to contribute to inferior mechanical properties, <i>e.g.</i>, strain at break, ε<sub>b</sub> < 20% for melt-molded specimens cooled at 38 °C/min, referred to as fast cooling. Addition of 1 wt % of E<sub>67</sub>X<sub>138</sub>E<sub>67</sub> to rPE and rPP led to improvements in ductility, dependent on the rate of cooling of melt-molded specimens. Fast cooling produced marginal gains in ductility, ε<sub>b</sub> ≈ 90 and 30% in rPE and rPP, respectively. However, industrially relevant very fast cooling (380 °C/min) dramatically improved the ductility, where ε<sub>b</sub> ≥ 500% for both recycled plastics. Similar results were obtained with virgin PE/PP blends containing 1 wt % E<sub>67</sub>X<sub>138</sub>E<sub>67</sub>. 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Enhancing Toughness of Post-Consumer Recycled Polyolefins with Polybutadiene-Derived Block Copolymers
There is a rapidly expanding need for economically viable approaches for ameliorating the wasteful disposal of post-consumer plastics in landfills and the leakage of these materials into the environment. Here, we assess the efficacy of poly(ethylene)-block-poly(ethylene-ran-ethyl ethylene)-block-poly(ethylene) (EXE) triblock copolymers as compatibilizers in post-consumer recycled poly(ethylene) (rPE) and isotactic polypropylene (rPP) containing ca. 10–15% PP and PE impurities, respectively. E67X138E67 was prepared by anionic polymerization of butadiene followed by catalytic hydrogenation, where the subscripts indicate block molecular weight in kg/mol. This triblock copolymer was mixed with rPE and rPP, along with blends formed from virgin PE and PP, and the recycled and blended materials were characterized by differential scanning calorimetry (DSC), atomic force microscopy (AFM), and tensile testing. The presence of phase-separated impurities in the recycled plastics was confirmed by DSC and AFM, and shown to contribute to inferior mechanical properties, e.g., strain at break, εb < 20% for melt-molded specimens cooled at 38 °C/min, referred to as fast cooling. Addition of 1 wt % of E67X138E67 to rPE and rPP led to improvements in ductility, dependent on the rate of cooling of melt-molded specimens. Fast cooling produced marginal gains in ductility, εb ≈ 90 and 30% in rPE and rPP, respectively. However, industrially relevant very fast cooling (380 °C/min) dramatically improved the ductility, where εb ≥ 500% for both recycled plastics. Similar results were obtained with virgin PE/PP blends containing 1 wt % E67X138E67. These findings are compared with the results described in a previous report, where 1 wt % E65X88E65 was added to virgin PE/PP blends, indicating that the X block molecular weight plays an important role in the efficacy of compatibilization.
期刊介绍:
ACS Applied Polymer Materials is an interdisciplinary journal publishing original research covering all aspects of engineering, chemistry, physics, and biology relevant to applications of polymers.
The journal is devoted to reports of new and original experimental and theoretical research of an applied nature that integrates fundamental knowledge in the areas of materials, engineering, physics, bioscience, polymer science and chemistry into important polymer applications. The journal is specifically interested in work that addresses relationships among structure, processing, morphology, chemistry, properties, and function as well as work that provide insights into mechanisms critical to the performance of the polymer for applications.