Back Cover: Micelles from thermoresponsive P(S‐b‐NIPAM‐b‐S) triblock copolymers show a decrease of their radius and subsequent aggregation when heated above the cloud point of PNIPAM. Time‐resolved small‐angle neutron scattering during a temperature jump unravels the kinetics of these processes and allows a quantitative description of the collapse and the aggregation. Further details can be found in the article by J. Adelsberger, E. Metwalli, A. Diethert, I. Grillo, A. M. Bivigou‐Koumba, A. Laschewsky, P. Müller‐Buschbaum, and C. M. Papadakis* .

A customized portable SAXS instrument has recently been constructed, installed, and tested at the D22 SANS instrument at ILL. Technical characteristics of this newly established plug-and-play SAXS system have recently been reported (J. Appl. Cryst. 2020, 53, 722). An optimized lead shielding arrangement on the SAXS system and a double energy threshold X-ray detector have been further implemented to substantially suppress the unavoidable high-energy gamma radiation background on the X-ray detector. The performance of the upgraded SAXS instrument has been examined systematically by determining background suppression factors (SFs) at various experimental conditions, including different neutron beam collimation lengths and X-ray sample-to-detector distances (SDDX-ray). Improved signal-to-noise ratio SAXS data enables combined SAXS and SANS measurements for all possible experimental conditions at the D22 instrument. Both SAXS and SANS data from the same sample volume can be fitted simultaneously using a common structural model, allowing unambiguous interpretation of the scattering data. Importantly, advanced in situ/real time investigations are possible, where both the SAXS and the SANS data can reveal time-resolved complementary nanoscale structural information.

Porous materials are widely used in applications such as adsorption, catalysis and separation. The use of expander molecules is a versatile route to enlarge the mesopore size in micellar templated...

The kinetics of water transfer between the lower critical solution temperature (LCST) and upper critical solution temperature (UCST) thermoresponsive blocks in about 10 nm thin films of a diblock copolymer is monitored by in situ neutron reflectivity. The UCST‐exhibiting block in the copolymer consists of the zwitterionic poly(4‐((3‐methacrylamidopropyl)dimethylammonio)butane‐1‐sulfonate), abbreviated as PSBP. The LCST‐exhibiting block consists of the nonionic poly(N‐isopropylacrylamide), abbreviated as PNIPAM. The as‐prepared PSBP80‐b‐PNIPAM400 films feature a three‐layer structure, i.e., PNIPAM, mixed PNIPAM and PSBP, and PSBP. Both blocks have similar transition temperatures (TTs), namely around 32 °C for PNIPAM, and around 35 °C for PSBP, and with a two‐step heating protocol (20 °C to 40 °C and 40 °C to 80 °C), both TTs are passed. The response to such a thermal stimulus turns out to be complex. Besides a three‐step process (shrinkage, rearrangement, and reswelling), a continuous transfer of D2O from the PNIPAM to the PSBP block is observed. Due to the existence of both, LCST and UCST blocks in the PSBP80‐b‐PNIPAM400 film, the water transfer from the contracting PNIPAM, and mixed layers to the expanding PSBP layer occurs. Thus, the hydration kinetics and thermal response differ markedly from a thermoresponsive polymer film with a single LCST transition.

Fullerene Intercalation In article number http://doi.wiley.com/10.1002/solr.201900508, Tobias Unruh and co‐workers report on the formation process of a PC60BM:pBTTT‐C14 active layer of a bulk heterojunction organic photovoltaic solar cell during evaporation of the solvent:additive mixture. By careful evaluation of the in‐situ grazing incidence small‐angle X‐ray scattering measurements, a conclusive picture of the 5‐step mechanism of fullerene intercalation and additive‐tuned evolution of the nanoscopic film structure during the drying process could be obtained.