Iberl Steffen, Voccia Maria, Ritacco Ida, Odenwald Lukas, Baur Maximilian, Falivene Laura, Caporaso Lucia, Mecking Stefan
Chair of Chemical Materials Science, Department of Chemistry, University of Konstanz, 78464 Konstanz, Germany.
Department of Chemistry, University of Salerno, Fisciano, Salerno 848048, Italy.
ACS Catal. 2025 May 2;15(10):8259-8267. doi: 10.1021/acscatal.5c00935. eCollection 2025 May 16.
Pd(II) phosphinosulfonate catalysts were employed in the nonalternating copolymerization of ethylene and carbon monoxide to produce keto-polyethylenes with high-density polyethylene-like materials properties. The different reactivities of the two monomers were addressed with a customized reactor setup that allows the feeding of ethylene and CO at very different feed ratios and automatic repressurization to replenish consumed monomers upon reaching a pressure threshold. Four literature-known catalysts were screened and the keto group microstructure of the resulting keto-PEs aligned well with the activation free energy differences (ΔΔG) of the alternating and nonalternating pathways, calculated via density functional theory. with a 2',6'-dimethoxy-1,1'-biphenyl-substituted phosphine motif was the most active catalyst, yielding copolymers with the highest molecular weight (around 30-40 kg mol). Consequently, was subjected to further optimization of the E/CO copolymerization to obtain HDPE-like materials. Tensile-testing specimens of keto-PEs with 0.5 and 1.4 mol % of keto groups were obtained via melt pressing and exhibited mechanical properties on par with the HDPE reference material.
钯（II）膦磺酸酯催化剂用于乙烯和一氧化碳的非交替共聚反应，以制备具有类似高密度聚乙烯材料性能的酮基聚乙烯。通过定制的反应器装置解决了两种单体不同的反应活性问题，该装置允许以非常不同的进料比进料乙烯和一氧化碳，并在达到压力阈值时自动重新加压以补充消耗的单体。筛选了四种文献中已知的催化剂，通过密度泛函理论计算得出，所得酮基聚乙烯的酮基微观结构与交替和非交替途径的活化自由能差（ΔΔG）吻合良好。具有2',6'-二甲氧基-1,1'-联苯取代膦基序的催化剂是活性最高的催化剂，可得到分子量最高（约30-40 kg/mol）的共聚物。因此，对乙烯/一氧化碳共聚反应进行了进一步优化以获得类似高密度聚乙烯的材料。通过熔融压制获得了酮基含量为0.5 mol%和1.4 mol%的酮基聚乙烯的拉伸测试样品，其机械性能与高密度聚乙烯参考材料相当。
