A Maximization of the Proton Conductivity of Sulfonated Poly(Ether Ether Ketone) with Grafted Segments Containing Multiple, Flexible Propanesulfonic Acid Groups.

To enhance the proton conductivity of sulfonated poly(ether ether ketone) (SPEEK), proton-conducting groups are required to be covalently connected to SPEEK and form proton-conducting channels. Herein, SPEEK fully grafted with segments containing multiple, flexible propanesulfonic acid groups (MS-SPEEK-102) is successfully prepared. Compared with SPEEK, MS-SPEEK-102 exhibits a higher proton conductivity of 8.3 × 10-2  S cm-1 at 80 °C with 98% relative humidity, and consequently a greater power density of 0.530 W cm-2 at 60 °C. These can be ascribed to the increased number of sulfonic acid groups, and ample, uninterrupted proton-conducting channels constructed by the movement of the maximum content, flexible side-chain segments. This approach offers an idea for obtaining a proton exchange membrane with good proton conductivity based on SPEEK.

Increased risk of mortality in systemic sclerosis-associated pulmonary hypertension: a systemic review and meta-analysis

Abstract Background: Pulmonary hypertension (PH) is a frequent complication of systemic sclerosis (SSc) and is currently one of the primary causes of death in patients with this disease. We conducted a systematic review and meta-analysis to assess the association between PH and mortality in patients with SSc to verify trends in mortality in patients with SSc-associated PH. Methods: We searched the PubMed and Embase databases for published studies on SSc-associated PH from inception to May 2021. All cohort studies in which mortality and/or survival for SSc-associated PH were reported were included in the analysis. The outcome parameters were pooled and analyzed using a random-effects model via generic inverse-variance weighting in conventional and cumulative meta-analysis. Results: The literature search identified 1161 citations, and the full texts of 54 studies were examined. Sixteen articles, with a total of 7857 patients with SSc and 1140 patients with SSc-associated PH, were included in the metaanalysis. Patients with SSc-associated PH had a higher pooled risk of mortality than patients with SSc without PH (risk ratio = 3.12; 95% confidence interval: [2.44, 3.98]). Conclusions: This meta-analysis revealed a higher mortality in patients with SSc-associated PH. PH was a significant predictor of death in patients with SSc. Thus, early diagnosis and treatment of PH are important in patients with SSc.