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With the growing requirement for lightweight structural materials in automotive, aerospace, and infrastructure applications, multi‐material joints made with adhesive have attracted intense research interest. Commercial thermoset adhesives are one‐time cures, and difficult to disassemble the bonded components for repair and recycling. Our prior work with a thermoplastic acrylonitrile‐butadiene‐lignin rubber (ABL) addresses this sustainability/recycling challenge, but the adhesive exhibits deficient joining strength compared to standard thermosets. Here, we modify the ABL matrix by loading particulate fillers to enhance its modulus and toughness. The goal is to manufacture a cure‐free thermoplastic adhesive system with a simple dispensing protocol and characteristic ductility combined with a high yield stress for improved shear strength of a bonded joint. Fumed silica (FS) and epoxidized glass spheres (EGS) were used as fillers in the ABL to promote the dispersion of lignin particles that tailored the functionalities and free energy components of the adhesive surface. With optimal loading of FS (5 wt%) and EGS (30 wt%) in the ABL adhesive matrix, the lap‐shear strength of the bonded aluminum joint was elevated by 128%, compared to the neat ABL, reaching 21 MPa, which is 90% of the performance of a commercial epoxy‐based adhesive. Highlights: A partly renewable filler‐toughened thermoplastic adhesive has been developed.This thermoplastic gives nearly equivalent performance of adhesively bonded aluminum joint compared to standard thermosets.Experimental and simulation data help understand the adhesive reinforcing mechanism by the fillers. [ABSTRACT FROM AUTHOR]

The cover image is based on the Research Article Acrylonitrile‐butadiene‐lignin thermoplastic rubber adhesive for enhanced metal‐to‐metal joining by Zeyang Yu et al., https://doi.org/10.1002/pc.28258. [ABSTRACT FROM AUTHOR]

The interface design plays a crucial role in developing superior mechanical performance of graphene nanoplatelets (GnP)/epoxy composite. Here, graphene oxide (GO) was applied as the coupling agent, because of π‐π interaction it formed with GnP and its rich surface functional groups. GO‐GnP couple was prepared and further it was treated separately with two diamines with different chain length (p‐phenylenediamine [PPDA] and Jeffamine D2000) producing functionalized GO‐GnP couple (f‐(GO‐GnP)). The chemical bonds formed between the amine functional groups on GO surface and epoxy resin during the curing process providing strong sheet/matrix interfacial adhesion. GO‐GnP/f‐(GO‐GnP) filler with two different weight ratios between GO and GnP (1:10 and 1:50) used as the fillers for preparing epoxy based composite with 0.43 and 0.86 wt% filler loading. For the tensile modulus, PPDA‐f‐(GO‐GnP: 1:10) sample gave ~40% improvement under 0.43 wt%, while at 0.86 wt%, the reinforcing result raised up to ~60% for PPDA‐f‐(GO‐GnP:1:50) sample. GO‐GnP couple/functionalized GO‐GnP couple gave up to ~110% improvement in toughness compared to simply using GnP at 0.86 wt% filler loading. [ABSTRACT FROM AUTHOR]

Objectives: Despite being a key population in whom to initiate pre‐exposure prophylaxis (PrEP), the awareness of and willingness to use PrEP are still unclear in Chinese young men who have sex with men (YMSM). We report factors associated with PrEP awareness and willingness in the population. Methods: From 1 August to 31 December 2018, 495 participants aged 15–24 years were included in a cross‐sectional study about awareness of and willingness to use PrEP among YMSM. Logistic regression models were used to identify factors associated with two outcomes: awareness of PrEP; and willingness to use PrEP. Results: Among 495 eligible participants, 129 participants (26.1%) knew about PrEP. PrEP awareness among YMSM was associated with higher education level [adjusted odds ratio (aOR) = 1.812, 95% CI: 1.113–2.951] and previous HIV testing (aOR = 3.507, 95% CI: 1.261–9.752). YMSM with shorter local residence time (aOR = 0.317, 95% CI: 0.101–0.992) and internet‐based partner‐seeking (aOR = 0.171, 95% CI: 0.096–0.305) were less likely to be aware of PrEP. In those with previous knowledge of PrEP, 36 (27.9%) conveyed their willingness to use it. PrEP willingness was associated with internet‐based partner‐seeking (aOR = 9.593, 95% CI: 1.965–46.844). The main barriers influencing those who knew about PrEP but refused to use it were the high price of PrEP (69.9%), the need to use condoms consistently (52.7%), and concerns about side effects (39.8%) and effectiveness of prevention (22.6%). Conclusions: Chinese YMSM have low awareness of and willingness to use PrEP. Adequate PrEP promotions should be implemented, especially on the Internet and dating software. [ABSTRACT FROM AUTHOR]