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1,3,3‐Trimethylspiroindoline‐2,3′‐3H‐naphth[2,1‐b][1,4]oxazine (1a) and 6′‐piperidino‐1,3,3‐trimethylspiroindoline‐2,3′‐3H‐naphth[2,1‐b][1,4]oxazine (1b) were applied as disperse dyes to polyester, nylon and acrylic fabrics. Under optimised dyeing conditions, photochromic fabrics were produced which, on irradiation with ultraviolet or exposure to sunlight, turned blue (1a) or blueish‐purple (1b). Dye 1a showed enhanced photochromic colour change performance compared with dye 1b. The photochromic colour build was highest on nylon and lowest on acrylic fabric. The colour change properties and the technical performance (wash fastness and photostability) of the photochromic fabrics were evaluated using specifically adapted colour measurement methods. The data were analysed in terms of variation of lightness, a*, b*, chroma, hue angle and ΔE, colour difference before and after exposure, and K/S curves as a function of irradiation time. The fabrics generally showed good wash fastness. Although the colour build‐up decreased with exposure to the Xenotest fadeometer, some residual photochromism remained after prolonged exposure.

The generation of a range of star-shaped block copolymers composed of a biocompatible poly(ethylene glycol) (PEG) core tethered to a polyalanine (PAla) shell that possesses the capability to (reversibly) self-assemble in water is described. The hydrogels formed offer a hydrophilic environment ideal for biological processes involving proteins and are able to withhold albumin for prolonged periods before its triggered release following the targeted material degradation by the proteolytic enzyme elastase. Consequently, the materials formed offer significant promise for the delivery of proteins, and possibly inhibitors, in response to a proteolytic enzyme overexpressed in chronic wounds.

Polyester, acrylic and nylon textile substrates dyed with two spirooxazine dyes, 1,3,3‐trimethyl‐spiroindoline‐2,3′‐3H‐naphth[2,1‐b][1,4]oxazine (1a) and 6′‐piperidino‐1,3,3‐trimethyl spiroindoline‐2,3′‐3H‐naphth[2,1‐b][1,4]oxazine (1b), exhibit significantly higher photochromic colour build‐up when wet compared with after drying. A study of this phenomenon, extended beyond water to the influence of a series of selected organic solvents on photochromic behaviour, using colour measurement of the photochromic textiles under controlled ultraviolet irradiation conditions, is reported. The results of molecular modelling calculations (AM1 in water and PM5 in water) have been used as a means of interpreting the observed effects, in conjunction with qualitative arguments based on solvation and fibre swelling.

Wool dyed with two isomeric water‐soluble spirooxazine‐based photochromic acid dyes, which were specifically designed and synthesised for direct application to protein and polyamide substrates, showed reversible change from a pale yellowish colour to blue when exposed to sunlight or UV light. With the first dye, significantly higher photochromic colour change was obtained when the wool was bleached, a feature attributed to a more open fibre structure which may facilitate penetration of the non‐planar dye anion and also the photocoloration reaction which requires a change in molecular geometry. Experimentation demonstrated that the optimum conditions for application of this dye to wool was from an aqueous dyebath at neutral pH and a temperature of 60 °C. An investigation using HPLC demonstrated that the dye was susceptible to decomposition in aqueous solution at higher temperatures and at lower pH values. The second dye was also applied to wool fabric to give a fabric with similar photochromic properties. The technical performance of the dyed fabrics, in terms of washfastness and photostability, was assessed.

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A systematic investigation was carried out to analyze the concentration levels of heavy metals in sample seawater, sediments, and biota collected from the coastal area of Yancheng City in Jiangsu Province, China. The authors assessed the impact of these heavy metals in different environmental samples in terms of potential risks to ecology and also to the human population exposed to this area. In addition, a further investigation was carried out to test the toxicity to early-life-stage zebrafish (Danio rerio) of selected samples that were considered to pose higher levels of potential risks to ecology or human health. Chemical analysis showed relatively higher concentrations of heavy metals in the seawater and biota samples collected from Xiangshui County and Binhai County, China. The heavy metal concentrations in different samples collected from the close vicinity of Dafeng Port, China, were also considerable. In all seawater and sediment samples, heavy metals showed a relatively moderate level of risk to ecological species; for consumption of marine organisms, heavy metals had adverse impacts on human health. Toxicity assessment indicated that the selected environmental samples or their extracts had significant toxicity to zebrafish early-life stages, including lethality, teratogenicity, and hatching delay (or advance). Thus the present study provides highly useful and important information on heavy metal pollution in Jiangsu Province.

(2014) 'Multihydroxyl end functional polyethylenes : synthesis, bulk and interfacial properties of polymer surfactants. ', Macromolecules., 47 (6). pp. 2062', Macromolecules., 47 (6). pp. -2071 Further information on publisher's website:http://dx.doi.org/10.1021/ma402158bPublisher's copyright statement:This document is the Accepted Manuscript version of a Published Work that appeared in nal form in Macromolecules, copyright c American Chemical Society after peer review and technical editing by the publisher. To access the nal edited and published work see http://dx.doi.org/10.1021/ma402158bAdditional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-pro t purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. for polar interfaces, are thermally stable up to ~ 250 °C, and to have similar crystallinity and dynamics to their unfunctionalised homopolymers analogues. The polymers segregated strongly to silicon oxide interfaces, with adsorbed layers forming spontaneously at annealed polymer interfaces, having surface excess concentrations approaching 2 R g , and a maximum areal density of approximately 0.6 adsorbed chains per nm 2 . This interfacial activity is achieved almost without detriment to the bulk physical properties of the polymer as evidenced by thermal analysis, quasi-elastic neutron scattering and smallangle neutron scattering (SANS). SANS experiments show little evidence for aggregation of the dihydroxyl functionalized polymers in blends with PE homopolymers, which is thought to explain why these additives have particularly strong interfacial adsorption, even at relatively high concentrations. A modest level of segregation of the additives to exposed blend surfaces was also seen, particularly when the additive molecular weight was significantly lower than that of the matrix. We attribute this to a combination of the relatively low molecular weight of the additives and the marginally lower surface energy associated with deuterated polymers.3