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Controlling the colloidal structure of multiphase latex particles offers a route to significant improvements in the mechanical properties of dried films for use in coatings. However, there is often conflict between the morphology that leads to optimum mechanical properties and the morphology that ensures good film formation at reduced temperatures. In this work, the case of two‐stage latex particles in which the second‐stage polymer has a high glass transition temperature (Tg) is considered. First, a number of different core/shell‐like particles with different polymer compositions and particle structures are synthesized by seeded semi‐batch emulsion polymerization. Using these latexes, the importance of phase mixing, particle morphology, and polymer composition with respect to film formation behavior and mechanical performance is discussed. The results highlight that in multiphase latex systems, the film formation behavior is dictated by the interplay between various colloidal and polymeric features of the samples. It is shown that understanding these features offers a route to systems that can match the film formation properties of a low Tg latex, whilst also approaching the mechanical properties of a high Tg polymer. The factors affecting film formation and mechanical properties of films cast from two‐stage latex particles are discussed. It is shown that a good balance between mechanical performance and film formation behavior can be achieved by targeting a core–shell structure containing a small fraction of high Tg polymer in the shell.

The use of polymer latexes for high‐performance coatings is challenging as the properties required to allow for film formation at reasonable temperatures tend to result in films with relatively poor mechanical properties. In this review, routes to overcome this so‐called film‐formation dilemma are discussed. First, the use of coalescing agents, focusing in particular on more recent approaches to minimize the use of volatile organic compounds (VOCs), is reviewed. Subsequently, approaches that utilize hybrid latexes are considered. This includes the use of high/low Tg latex blends, nanocomposites that include a second, non‐polymeric phase, and multiphase latexes. Finally, the use of crosslinking technologies is considered, with a focus on necessary developments to reduce environmental impact. The review concludes with a summary and a discussion of possible future directions for research. Achieving high‐performance waterborne coatings is challenging as the properties required to allow for film formation at reasonable temperatures tend to result in films with relatively poor mechanical properties. In this review, routes to overcome this so‐called film‐formation dilemma (volatile organic compound [VOC]‐free diffusion promotors, structural reinforcement, and chemical and physical crosslinking) are discussed.

Polyphenol or multihydroxybenzene compounds show great potential as electrode material for organic batteries. Among them, 1,2,3,4‐tetrahydroxybenezene is the best candidate as a high‐specific capacity material due to its potential to exchange up to four electrons. To further corroborate this, we synthesized a model compound and carry out electrochemical characterization. Quasi‐reversible redox behavior, similar to other hydroxybenzene materials, was obtained in an acidic aqueous electrolyte. The four electron exchange was further confirmed by using reduced and oxidized model compounds, which showed comparable electrochemical behavior. Additionally, we prepared insoluble nano sized polymer based on poly(2,3,4,5‐tetrahydroxystyrene) which was used as a cathode material in an organic battery. Initial results suggested that these tetrahyroxybenzene polymers are very promising for proton batteries in acidic aqueous electrolytes, whereas their performance in lithium batteries is limited. 1,2,3,4‐tetrahydroxybenzene seems to be the best candidate among polyphenols to prepare high energy organic positive materials (cathodes). In this article all three redox states are prepared and fully characterized. Their electrochemistry is tested in various electrolytes, compared altogether and redox mechanism proposed. Finally redox polymer is prepared and tested in Li in Zn battery.

Water-based (meth)acrylic (co)polymer dispersions are produced on a large scale for various applications including coatings, adhesives, paints, and construction materials. A major benefit of waterborne polymer dispersions as compared to more traditional solvent-based alternatives is the low volatile organic compound (VOC) content, which results in an improved environmental profile. Following the trend of sustainability that has driven the growth of acrylic dispersions, recent research has focused on further enhancing the properties of these products by incorporating biobased materials such as polysaccharides (e.g., cellulose, starch, chitin, and chitosan), and proteins (e.g., casein, soy protein, and collagen). Amongst a large number of benefits, the incorporation of biomaterials can serve to decrease the amount of petroleum-based polymers in the formulation and can also contribute to enhance the physical properties of the resulting bio-composites. In this review, the beneficial role of these biopolymers when combined with waterborne acrylic systems is summarized. Recent advances in the use of these biobased and biodegradable materials are covered, aiming to provide guidance for the development of more sustainable, high-performance latex-based bio-composites with minimal environmental impact.

The occurrence of intramolecular transfer to polymer in the radical polymerization of acrylic monomers has been extensively documented in the literature. Whilst it has been largely assumed that intramolecular transfer to polymer leads to short chain branches, there has been some speculation over whether the mid-chain radical can migrate. Herein, by the matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry (MS) of poly(n-butyl acrylate) synthesized by solution polymerization under a range of conditions, it is shown that this mid-chain radical migration does occur in the radical polymerization of acrylates conducted at high temperatures, as is evident from the shape of the molecular weight distribution. Using a mathematical model, an initial approximation of the rate at which migration occurs is made and the distribution of branching lengths formed in this scenario is explored. It is shown that the polymerizations carried out under a low monomer concentration and at high temperatures are particularly prone to radical migration reactions, which may affect the rheological properties of the polymer.

We have shown new applications and synthetic routes for polymer colloids in the field of home and personal care products by controlling polymer and/or colloidal architectures. Our initial aim was to develop functional particles that imparted beneficial properties to fibrous substrates and as such our first goal was to develop a method for depositing particles onto such surfaces. Chapter 2 describes the method by which we achieved this goal, namely adding a small amount of a low glass transition polymer to an otherwise non-adhesive polymer to enhance colloidal deposition. Following on from this work we looked into ways in which to impart desirable characteristics from the particles onto fibres. In Chapter 3 we describe how the use of a hydrazide functional monomer in polymer gels can provide a continuing slow release of fragrance molecules that reacts to the environment it is held in such that if the local fragrance concentration is low then more is released. In Chapter 4 we describe the synthesis of highly porous particles with controlled pore sizes and the use of such particles in oil absorption for applications in water-free cleaning systems. The particles are capable of carrying many times their own weight in oil and are shown to be reusable. In Chapter 5 we describe a computational model that predicts the ability of a particle to stabilize emulsions. The model is highly adaptable and can be used to predict the surface activity of almost any particle morphology. Chapter 6 builds on this work and described the synthesis of highly anisotropic polymer particles by templating preexisting structures and explains their surface activity, or lack thereof.

Pressure-sensitive adhesives (PSAs) are soft polymeric materials that exhibit complex rheological and mechanical behavior gov- erned by the interplay between polymer architecture, crosslink density, and entanglement constraints. Predicting their rheological properties from underlying microstructure remains a central challenge in adhesive design. In this work, we adopt a multiscale com- putational framework based on the Lagrangian Heterogeneous Multiscale Method (LHMM), coupling a macroscopic continuum description with a mesoscale polymer network model featuring breakable bonds embedded in a viscous medium. The approach enables consistent information transfer across scales and captures both elastic network response and viscous dissipation. The framework is calibrated using experimental rheological data and tensile measurements for four PSA formulations with varying gel fractions and crosslink densities. The simulations reproduce key experimental trends in storage modulus (G'), loss modulus (G\"), and tensile stress-strain behavior under planar extension, while differentiating the distinct mechanical signatures of each formula- tion. The results elucidate how crosslink density and effective network connectivity control stiffness, stress localization, and failure characteristics. Overall, the proposed multiscale methodology provides a predictive platform for linking microstructural design pa- rameters to macroscopic mechanical properties and offers a rational basis for the formulation and optimization of next-generation PSAs.

An overview on high-resolution and fast interrogation of optical-fiber sensors relying on laser reflection spectroscopy is given. Fiber Bragg-gratings (FBGs) and FBG resonators built in fibers of different types are used for strain, temperature and acceleration measurements using heterodyne-detection and optical frequency-locking techniques. Silica fiber-ring cavities are used for chemical sensing based on evanescent-wave spectroscopy. Various arrangements for signal recovery and noise reduction, as an extension of most typical spectroscopic techniques, are illustrated and results on detection performances are presented.

Blood biomarkers are rapidly becoming established for Alzheimer’s Disease (AD) diagnosis. However, there is a need for more scalable tools to reach the 99% of individuals with early cognitive impairment who are not seen in specialist healthcare services. A recent study validated a capillary blood sampling technique to detect the p-tau217 and GFAP biomarkers. Here we used our PROTECT research study to show that these biomarkers, when collected using self-administered fingerprick tests, correlate well with venous blood biomarkers and with cognition and function in 174 people who were cognitively normal or who had mild cognitive impairment or AD. They can be used in combination with computerised cognitive testing to identify people with the highest risk of AD. The GFAP biomarker appears to be associated with vascular risk, unlike p-tau217. Patient feedback indicates high acceptability and usability of the capillary test method, giving confidence in the feasibility of this technology. The work suggests that capillary blood biomarkers could be used to enable triage of people with varying levels of risk of AD in clinical practice and for clinical trials, and could be used outside of clinical settings. This study shows that capillary blood sampling at home using fingerprick testing is feasible and provides reliable biomarkers for Alzheimer’s Disease. They correlate with cognition and can identify people at highest risk of Alzheimer’s Disease.

The study determined the one year incidence of post operative cognitive decline (POCD) and evaluated the effectiveness of an intra-operative anaesthetic intervention in reducing post-operative cognitive impairment in older adults (over 60 years of age) undergoing elective orthopaedic or abdominal surgery. The design was a prospective cohort study with a nested randomised, controlled intervention trial, using intra-operative BiSpectral index and cerebral oxygen saturation monitoring to enable optimisation of anaesthesia depth and cerebral oxygen saturation in older adults undergoing surgery. In the 52 week prospective cohort study (192 surgical patients and 138 controls), mild (χ(2) = 17.9 p<0.0001), moderate (χ(2) = 7.8 p = 0.005) and severe (χ(2) = 5.1 p = 0.02) POCD were all significantly higher after 52 weeks in the surgical patients than among the age matched controls. In the nested RCT, 81 patients were randomized, 73 contributing to the data analysis (34 intervention, 39 control). In the intervention group mild POCD was significantly reduced at 1, 12 and 52 weeks (Fisher's Exact Test p = 0.018, χ(2) = 5.1 p = 0.02 and χ(2) = 5.9 p = 0.015), and moderate POCD was reduced at 1 and 52 weeks (χ(2) = 4.4 p = 0·037 and χ(2) = 5.4 p = 0.02). In addition there was significant improvement in reaction time at all time-points (Vigilance Reaction Time MWU Z = -2.1 p = 0.03, MWU Z = -2.7 p = 0.004, MWU Z = -3.0 p = 0.005), in MMSE at one and 52 weeks (MWU Z = -2.9 p = 0.003, MWU Z = -3.3 p = 0.001), and in executive function at 12 and 52 weeks (Trail Making MWU Z = -2.4 p = .0.018, MWU Z = -2.4 p = 0.019). POCD is common and persistent in older adults following surgery. The results of the nested RCT indicate the potential benefits of intra-operative monitoring of anaesthetic depth and cerebral oxygenation as a pragmatic intervention to reduce post-operative cognitive impairment. Controlled-Trials.com ISRCTN39503939.