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The purpose of this study is to prepare nanoscale copolymer-silicon dioxide (SiO₂) dispersion for formulating textile printing white ink.

Nanoscale copolymer-SiO₂ dispersion was prepared via miniemulsion polymerization. The miniemulsion formulation was optimized for preparing stable SiO₂/O/W miniemulsion and nanoscale copolymer-SiO₂ dispersion. The nanoscale copolymer-SiO₂ was investigated by transmission electron microscope (TEM), X-ray diffraction (XRD), differential thermal gravity (DTG) and thermogravimetric analysis (TGA). The performance of white inks from this colorant was further investigated.

Nanoscale copolymer-SiO₂ had a core-shell structure with about 45 nm encapsulated copolymer layer when it was synthesized under optimal miniemulsion formulation 60 per cent mass ratio of styrene (St) to KH570-SiO₂, 5.0 per cent hexadecane to St and 2.0 per cent concentration of DNS-86. The nanoscale copolymer-SiO₂ white ink had high thermal and centrifugal stability with high purity and color fastness.

The miniemulsion polymerization conditions required a careful control before favorable results could be achieved.

The nanoscale copolymer-SiO₂ dispersion and white ink prepared by this method showed excellent stability. This research could accelerate the textiles inkjet printing application.

The reactive stabilizer DNS-86 is innovatively introduced into the miniemulsion polymerization to improve the stability of the nanoscale copolymer-SiO₂ dispersion. The white ink was formulated from nanoscale copolymer-SiO2 to improve the fastness of the printed fabrics.

The purpose of this study is to find the multi-factor influence law of stress, strain rate and sulfate-reducing bacteria (SRB) on X70 pipeline steel in a simulated solution of sea mud and the order of influence of the three factors on X70 steel to develop a scientific basis for pipeline corrosion protection.

This paper studied the effects of stress, strain rate and SRB on the X70 pipeline steel corrosion behavior in simulated sea mud solution through orthogonal testing, electrochemical experiments and morphological observations.

The results of this study showed that stress proved to be the most relevant element for corrosion behavior, followed by SRB and strain rate. At high stresses (301 MPa and 576 MPa), stress dominated the corrosion behavior of X70 pipeline steel. However, at low stress (82 MPa), SRB played the most important role.

Subsea pipelines are in a very complex environmental regime that includes stress, strain rates and SRB, which often cause pipeline pitting and perforation. However, most scholars have only looked into the influence of single factors on metal corrosion. So, the single-factor experimental results of previous studies could hardly be applied to actual working conditions. There is an urgent need to understand the multi-factor influence law of stress, strain and SRB acting together on the pipeline corrosion behavior, especially to determine the dominant factor.

This study aims to investigate the effect of microtextured tools on the geometric morphology of serrated chips, and further improve the cutting performance of polycrystalline cubic boron nitride (PCBN) tool and extend the tool life and the surface quality of the machined surface.

A three-dimensional finite element cutting model of hardened steel AISI D2 with microtextured PCBN tools were established using the finite element software Abaqus, and cutting tests were carried out. Furthermore, the stress distribution in the primary deformation zone was investigated based on the triaxiality of stress, and the influence of microtexture on the geometric morphology of serrated chips and crack development was researched.

The results show that compared with nontexture tools, elliptical pits and wavy grooves microtexture tools have lower serrated degree Gs, higher serrated frequency f per unit length and more miniature serrated step Pc. The serrated phenomenon is intensified because the tensile stress zone of chips generated by nontextured tools is longer than that of elliptic pits and wavy grooves microtexture tools. Simultaneously, the maximum value of triaxiality in the tensile stress zone achieved by nontexture tools is larger than that of the two microtexture tools, and chips obtained by nontextured tools are more susceptible to propagation fractures.

This paper mainly studies the effect of microtexture on chip microgeometry, which is relatively little studied at present. At the same time, this paper has a certain engineering significance for PCBN tool turning hardening steel.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2023-0149/