MAIN STANDARD INDICATORS OF POLYMER ASPHALT CONCRETES

The main indicators of 29 types of asphalt and polymer asphalt concretes prepared with the use of neat bitumens of 2 grades and 7 types of polymer bitumens have been determined and comparatively analyzed in the work. The bitumens of grades BND 100/130 and BND 130/200 produced by the Pavlodar petrochemical plant have been selected for preparation of the asphalt concretes, polymer bitumens and polymer asphalt concretes. 7 types of the polymers (Elvaloy 4170, Elvaloy AM, Kraton D 1192A, Calprene 501, SBS L 30-01 A, KUMHO KTR, Butonal NS 198) have been selected for the modification of the bitumens. Short procedure has been represented for the preparation of the polymer bitumens. 29 types of the asphalt and the polymer asphalt concretes have been prepared with the use of the above bitumens and polymer bitumens (asphalt concrete of type A - 7, asphalt concrete of type B - 15, stone mastic asphalt concrete SMA-15 - 1, stone mastic asphalt concrete SMA-20 - 6). The following main indicators of quality have been determined for the asphalt concretes and polymer asphalt concretes by testing in relevant laboratory devices: 1) rut depth at the temperature of 60 °С after 10 000 passages of the wheel (ST RK EN 12697-22-2012); 2) tensile strength at the temperature of -30 °С (pr. EN 12697-46-2012); 3) compression strength at the temperature of 50 °С (ST RK 1218-2003); 4) water saturation (ST RK 1218-2003). It is found out that the modification of the bitumens with the polymers increases essentially the main standard indicators of the asphalt concretes: rutting resistance, strength at high temperatures and low temperatures, resistance to the cyclic freezing and thawing (frost resistance). The reactive polymers Elvaloy 4170 and Elvaloy AM are the most efficient among the used ones.

BITUMENS AND POLYMER BITUMENS - NANODISPERSE SYSTEMS

This work shows the data regarding the elemental and chemical group compositions of the road bitumens. The short characteristic has been shown for the components of the bitumens - the asphaltenes, the resins and the oils. The properties have been described for the bitumens on which they have the direct impact. The description is given for the micellar model of the bitumens from the point of view of the colloid chemistry. The analysis has been performed for the results of the study by other authors for the asphaltenes of a bitumen and an oil. The group chemical compositions are given for the bitumen of the grades BND 50/70, BND 70/100 and BND 100/130 produced by the plants of Kazakhstan. It has been shown that the content of the asphaltenes in them is from 15.8% to 24.3%; in most cases, the content of the asphaltenes is within the range of 20-25%, i.e. the asphaltenes nanoclusters are almost a fourth of the bitumen by weight. The brief description is given for the best known polymers used for the modification of the road bitumen: 1) the reactive polymers Elvaloy 4170 and Elvaloy AM; 2) the polymers of the group SBS - Kraton D 1192A, Calprene 501, SBS L 30-01 A, KUMHO KTR and Butonal NS 198. It is proposed to consider the bitumen and the polymer bitumen as the peculiar nanodisperse systems. The structures are described for the polymer bitumen nanodisperse systems occurring during the modification of the road bitumen with the polymers of the above two groups.

Self-limiting directional nanoparticle bonding governed by reaction stoichiometry

Nanoparticle clusters with molecular-like configurations are an emerging class of colloidal materials. Particles decorated with attractive surface patches acting as analogs of functional groups are used to assemble colloidal molecules (CMs); however, high-yield generation of patchy nanoparticles remains a challenge. We show that for nanoparticles capped with complementary reactive polymers, a stoichiometric reaction leads to reorganization of the uniform ligand shell and self-limiting nanoparticle bonding, whereas electrostatic repulsion between colloidal bonds governs CM symmetry. This mechanism enables high-yield CM generation and their programmable organization in hierarchical nanostructures. Our work bridges the gap between covalent bonding taking place at an atomic level and colloidal bonding occurring at the length scale two orders of magnitude larger and broadens the methods for nanomaterial fabrication.

Self-crosslinkable polymers from furan-functionalized Meldrum's acid and maleimides as effective precursors of free-standing and flexible crosslinked polymer films showing low dielectric constants

The integration of Michael addition and Diels–Alder reaction in the synthesis of reactive polymers for self-standing and flexible crosslinked polymer films.

Thiol-reactive thiosulfonate group containing copolymers: facile entry to disulfide-mediated polymer conjugation and redox-responsive functionalizable networks

Herein, we report a synthetic approach to thiol-reactive polymers containing methanethiosulfonate groups as side chains, and demonstrate their application in post-polymerization functionalization through reversible disulfide linkages.

Simultaneous Evaluation of Multiple Microarray Surface Chemistries Through Real-Time Interferometric Imaging

<p>Surface chemistry is one of the most crucial aspects for microarray modality biosensor development. As a matter of fact, the immobilization capability of the functionalized surface is one of the limiting factors for the final yield of the binding reaction. In this work, we locally deposited many reactive polymers on a single solid support, allowing for a direct comparison of functionality of probes immobilized on different polymers and demonstrating a new way of multiplexing. Our goal was to investigate the immobilization efficiency of reactive polymers, as well as the resulting affinity of the molecular probes, in a single experiment. This idea was demonstrated by spotting a large number of different reactive polymers on an untreated Si/SiO₂ chip, and depositing the same molecular probe on all the spots immediately after. This method proved to be efficient and could be used as an initial qualitative assay to decide which functionalization better suits a certain application. We also showed that the localized functionalization method is applicable to proteins as well as oligonucleotides. Moreover, by means of real-time binding measurements performed with the Interferometric Reflectance Imaging Sensor (IRIS), we demonstrated that this functionalization technique is comparable to the uniformity of classical flat-coating solution. The comparison between the binding curves that were obtained from different polymer spots with the same probe allowed us to decide which polymers would work better to immobilize a model protein, α-Lactalbumin, as well as a peptide extracted from the latter, namely LAC-1. The final outcome is promising, and it highlights the multiplexing power of this method: first, it allows to characterize dozens of polymers at once, within a single 60-minutes experiment. Secondly, it removes the limitation, related to coated surfaces, that only molecules with the same functional groups can be tethered to the same solid support. By applying this innovative protocol, there is no more restriction on the type of molecules that can be studied simultaneously and immobilization for each molecular probe can be individually optimized.</p>