Three compounding methods were compared to determine their effects on the organization of the interphase in nanocomposites of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and cellulose nanocrystals (CNCs) processed via (1) direct compounding, (2) reactive extrusion using a coupling agent (PHBV-g-GMA), or (3) reactive extrusion using a peroxide free-radical initiator (dicumyl peroxide,
sergio.rodrigues@xenocs.com27 January 2020
The synthesis of ZnO nanoparticles proceeds through a complex sequence of precursor reactions, nucleation, and growth processes. For further advancement and control of nanoparticle synthesis, a detailed understanding of the mechanisms and kinetics is essential. With the recent advancement in X-ray scattering and spectroscopy methods, in situ experiments during nanoparticle…
sergio.rodrigues@xenocs.com27 January 2020
The behavior of photochromic spiropyran (SP) dyes is greatly affected by the local environment in which they reside. Fluid microenvironments such as liquidlike polymers grant favorably fast dye decoloration whereas rigid microenvironments such as glassy polymers inhibit fast dye response. We study the use of disorganized but microphase-separated block polymer…
sergio.rodrigues@xenocs.com27 January 2020
Thiols play an important role in the synthesis of well-defined nanoparticles (NPs) with tailored properties, but their effects on the formation kinetics of NPs are still under investigation. Here, we used in situ small-angle X-ray scattering (SAXS)/UVvis spectroscopy and time-dependent transmission electron microscopy (TEM) to elucidate the role of thiols…
sergio.rodrigues@xenocs.com27 January 2020
In this work, we report on the synthesis of a series of polyesters based on 1,6-hexanediol, sebacic acid, and N,N’-dimethylene-bis(pyrrolidone-4-carboxylic acid) (BP-C2), of which the latter is derived from renewable itaconic acid and 1,2-ethanediamine. Copolymers with a varying amount of BP-C2 as dicarboxylic acid are synthesized using a melt-polycondensation reaction…
sergio.rodrigues@xenocs.com27 January 2020
The length of pendant side chains in charged, random, comb-shaped polymers dictates the nature of their short-range ordering. Random copolymers, and terpolymer, of 4-vinylpyridine (4VP), styrene, and isoprene were synthesized and subsequently fully quaternized with 1-alkylbromides having varying number of carbons on the alkyl group ranging from 2 to 8.…
sergio.rodrigues@xenocs.com27 January 2020
High axial aspect crystalline nanomaterials have emerged as polymeric building blocks for the construction of supermaterials. In contrast to this form, amorphous nanospheres have remained largely untapped. This is especially peculiar in the context of material assembly, due to the wide range of opportunities they offer by virtue of their…
sergio.rodrigues@xenocs.com27 January 2020
Magnetosomes are membrane-enveloped single-domain ferromagnetic nanoparticles enabling the navigation of magnetotactic bacteria along magnetic field lines. Strict control over each step of biomineralization generates particles of high crystallinity, strong magnetization, and remarkable uniformity in size and shape, which is particularly interesting for many biomedical and biotechnological
sergio.rodrigues@xenocs.com27 January 2020
Atomically precise thiolate-gold nanoclusters with well-defined structures attract attention for use in various applications. However, most of the recently reported synthetic methods rely on prolonged synthesis times (a few hours to days) in order to produce high purity materials with a single cluster size. Such extended synthesis times make these…
sergio.rodrigues@xenocs.com27 January 2020
Building the desirable superstructure of polyethylene is one of the important topics for developing high value-added products, which brings potential benefits for society and sustainable development. Crystalline order is the ubiquitous superstructure for enhancing mechanical properties of polymeric materials. In this work, polystyrene copolymers (c-PS) are incorporated into pores of…
sergio.rodrigues@xenocs.com27 January 2020