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The purpose of this paper is to provide a critical and in‐depth review of the present status and recent developments in synthetic methodologies, reaction engineering, process design and quality control aspects associated with the manufacture of mono and multifunctional acrylate monomers.

This paper reviews commercially important UV cure mono and multifunctional acrylate monomers. It covers their synthesis, catalyst, and appropriate solvents for azeotropic removal of byproducts. The detail discussion on catalysis, basis of design of reactors and commercial plant and the process engineering associated with the manufacture has been supported through citation of synthesis of various acrylate monomers. The methodologies adopted for determination of physical, chemical and compositional characterisation of acrylate monomers have been presented. In addition, the guidelines regarding the bulk storage and commercial handling of acrylates have been reviewed.

The reaction engineering of esterification reaction between acrylic acid and polyol has been worked out to provide the basis for selection of reactors. The reaction has been modeled as a series – parallel complex reaction for providing explanation for generation of various byproducts/adducts and multiple esters.

The detailed discussion on formation, characterisation and treatment of Michael adducts and purification of acrylate monomers will be relevant for new researchers for further development. A review of guidelines on selection of homogenous and heterogeneous catalysts for synthesis of acrylate monomers has been presented.

Since the related literature on acrylate monomers is scarce, scattered and proprietary, the consolidated coverage in one paper will be useful.

The purpose of this work was to study the effect of chemical structure of reactive diluents on the curing behaviour and physical–mechanical properties of a titanium dioxide pigmented UV-curable epoxy acrylate system.

Two different tri-functional and two different tetra-functional acrylate monomers were used as reactive diluents in the formulations. The curing behaviour of the formulations was studied by using photo-differential scanning calorimetry analysis. The rate of curing, conversion at the maximum rate and ultimate conversion for different formulations were calculated. In addition, the physical and mechanical characteristics of the cured films, including glass transition temperature and modulus, were measured by using a dynamic mechanical analysis technique.

The results showed that the ultimate conversion for non-pigmented pentaerythritol triacrylate (PETA) and trimethylol propane triacrylate (TMPTA) formulations were almost similar, but the interference effect of titanium dioxide particles on the curing of the PETA formulations was found to be more considerable in comparison to the TMPTA formulations. The extent of reaction for tetra-functional acrylate monomers was considerably less than those for tri-functional acrylate monomers. The Tg and storage modulus of non-pigmented PETA, TMPTA and pentaerythritol tetraacrylate (PE4TA) formulations were almost the same and higher than that for ditrimethylol propane tetraacrylate (DiTMP4TA) formulations. However, Tg and storage modulus of pigmented tetra-functional acrylate monomer formulations were higher than those for tri-acrylate monomer formulations.

The curing conditions (temperature and UV intensity) can affect the network formation and consequently will affect on the properties of the cured films.

The pigmented UV-curable coatings are interested for many industries such as wood and automotive industries. The reported data can be used by the formulators working in the R&D departments. In addition, the results obtained can be used by the researchers who are active in the field of structure–property relationship for UV-curable coatings.

UV-curing systems are considered as one of the most environment-friendly coatings system. Therefore, the developing of its knowledge can help to extend its usage to different applications.

The photopolymerisation of pigmented coatings is a great challenge and is hardly investigated in the literature. Therefore, in this research, the effect of chemical structure and functionality of different multifunctional acrylate monomers on the curing behaviour of pigmented formulations was investigated.

The purpose of this work was to perform a systematic study on the effect of formulation on the physical and mechanical properties of ultaviolet (UV) curable urethane acrylate resins. In addition, the authors wanted to derive mathematical formula for the prediction of physical and mechanical properties for the aforementioned system.

The experiments were carried out based on mixture experimental design to determine the effect of different multifunctional acrylates (i.e. 1,6-hexanediol diacrylate (HDDA), tripropylene glycol diacrylate (TPGDA), trimethyolpropane triactylate (TMPTA)) concentration on the physical and mechanical properties of a UV curable polyurethane acrylate system. The urethane oligomer was synthesized and characterized by the research team. Microhardness, adhesion strength and scratch resistance of the cured films were evaluated as the physical and mechanical properties.

The results revealed that the resin and TMPTA concentrations had the most significant effects on the microhardness property. Adhesion strength of the films showed a linear trend with respect to all variables. Moreover, all components also had a significant and complex influence on the scratch resistance of the cured systems. In addition, mathematical equations proposed by mixture experimental design were derived for all the mentioned properties.

Other multifunctional acrylate monomers (i.e. more than three functional) can be used in the formulations. The kinetics of the curing can affect on the network formation and consequently on the properties of the cured films.

The obtained results can be used by the researchers who are active in the field of structure-property relationship of polymers and surface coatings. The reported data and the mathematical equations can also be used for the formulating of an appropriate formulation based on a specific application.

A systematic and statistical-based approach, i.e. mixture experimental design, was used to evaluate the effect of formulation on some of the properties of a UV curable polyurethane acrylate system. A urethane oligomer and three different multifunctional acrylate monomers as reactive diluents were used in the formulations. Noteworthy to mention that several mathematical models were derived by using analysis of variance for the prediction of the properties studied in this system.

Urethane Acrylate Oligomer with 100% solids was synthesised and characterised in order to study the application in electron beam curing with varying ratio of Trimethylol propane triacrylate (TMPTA). The purpose of this paper is to study effect of TMPTA addition on the crosslink density and different coating properties.

Polyester polyol was synthesised by reacting single diacid, adipic acid (AA), with Pentaerythritol (PENTA) and 1,6‐hexanediol (HD). Further, Urethane acrylate resin was synthesised by using Isophorone diisocyanate (IPDI), hydroxy ethyl acrylate (HEA) and Polyester polyol. The polyester polyol and urethane acrylate oligomer were characterised by 1H NMR, 13C NMR, FTIR and GPC. Further, TMPTA was added as a crosslinker to the urethane acrylate oligomer and cured by electron beam radiation. The cured UA films having varying concentration of TMPTA were employed to evaluate thermal property, contact angle analysis, mechanical and chemical properties.

The obtained results showed improvement in their chemical properties, mechanical properties, thermal properties and water contact angle at 20% of TMPTA iconcentration. The TMPTA also reduced the dose required for the curing.

The resin can be synthesised from different isocyanates as TDI, MDI and HMDI, etc. The study can also be done with different multi or mono functional monomers such as methacrylate, hexanediol diacrylate, ethylene glycol diacrylate, etc.

The paper provides the better solution to reduce the cost of the electron beam radiation required for the curing.

The method presented in the paper could be very useful for controlling environmental pollution; as the conventional method of curing releases volatile organic compounds (VOC).

In this paper, urethane acrylate and TMTPA cured with electron beam are shown to offer good coating properties. A high‐solid urethane acrylate coating would find numerous industrial applications in surface coatings.

The purpose of this work is to develop flexible as well as rigid polyurethane coating by using mixed polyol. It is developed by using low cost reactant such as polyether and introducing branching in it.

Radiation curable branched polyurethanes were synthesised. In this work, branched polyol was synthesised by using trimethylol propane (TMP) and reacted with adipic acid (AA), neopentyl glycol (NPG) (polyester) and polypropylene glycol (PPG) (polyether). These branched polyols were developed by varying ratio of polyether to polyester from 20:80, 40:60 and 55:45. These branched polyols were further reacted with isophorane di isocyanate (IPDI) and hydroxy ethyl metha acrylate (HEMA) to get vinyl terminated prepolymer.

The branched polyol due to presence of polyether offers excellent flexibility and polyester which provides excellent scratch, adhesion, and tensile strength. Use of reactive diluents is avoided, and its role is compensated by polyether in all systems, which takes care of reducing viscosity and improves flow and levelling properties.

Synthesis of branched polyol using polyesters and polyethers is more beneficial as it offers advantage of its combined property.

The polyurethane acrylate due to its polyol combination, branching and cross linking offers enhanced coating properties and can be used for various coating applications.

UV‐radiation curing has become a well accepted technology which has found its main applications in the coating industry, the graphic arts and microelectronics. The liquid to solid phase change proceeds within a fraction of a second on intense illumination at ambient temperature. The kinetics of such ultrafast polymerization have been followed in situ by real‐time infrared spectroscopy. This technique proved well suited to assess the performance of the various constituents of a UV‐curable formulation (photoinitiator, monomer, functionalized oligomer) from measurements of the actual polymerization rate and of the final cure extent. The photopolymerization of both radical‐type (acrylates) and cationic type (epoxides, vinyl ethers) monomers has been examined, as well as that of monomer blends. Interpenetrating polymer networks have been synthetized by photocrosslinking of a hybrid acrylate/epoxide system which generates a hard and scratch‐resistant polymer material.

The purpose of this paper is to synthesise UV curable emulsion latex and to study characteristics and various performance properties such as tackiness, peel adhesion and cohesive strength for pressure sensitive adhesive (PSA) application after UV curing.

The two component water‐based ultraviolet (UV) curable acrylate PSAs were synthesised by emulsion copolymerization. The synthesised emulsion samples were characterised and various performance properties such as tackiness, peel adhesion and cohesive strength for PSAs were tested after UV curing.

The thermal analysis showed the effect of methyl methacrylate (MMA) content on the glass transition temperature of emulsions, which had significant effect on tack. Effects of varying concentration of multifunctional monomer trimethylolpropane triacrylate (TMPTA) and UV exposure time on properties of UV curable PSA were also studied.

The results associated with the UV curable water based PSA has certain advantages, such as low VOC and fast curing rate and with the scope for further research by using the radiations with different intensities or other radiation systems such as electron beam curing.

Practically the UV water based PSAs are already in industrial use for glass lamination, silicon semiconductor dicing, and in medical use for band aids and drug delivery systems and for dental applications for cavity filling.

The water based UV curable PSA synthesised by emulsion polymerization had very good tackiness properties with lower MMA content. It was observed that the lower the concentration of TMPTA, the better the performance properties, such as tack and peel strength. It was also observed that with increasing TMPTA concentration the cohesive strength increased.

To determine the optimal general condition for the synthesis and polymerisation of 2‐(N‐phthalimido)ethyl acrylate (NPEA), as well as the exchange reactions of poly‐NPEA with aminated and hydroxylated compounds as a model compound.

Preparation of 2‐(N‐phthalimido)ethyl acrylate by the reaction of N‐(2‐hydroxyethyl) phthalimide with acrylic acid and polymerisation of the resulting monomer. The exchange reactions of the resulting polymer with amines and hydroxy compounds were carried out. The structure of the resulting compounds were characterised.

NPEA was prepared by the reaction of N‐(hydroxyethyl)phthalimide with acrylic acid. The monomer prepared was easily polymerised. The reactions of the resulting polymer with amines and hydroxy compounds were studied. In all cases, the exchange reactions were almost practically quantitative, which was confirmed by elemental analysis, IR and ¹HNMR spectroscopy. Also, it was clear that poly‐NPEA showed a good behaviour as a model compound for a long active polymeric‐drug.

The new monomer described in the present investigation may be useful for the preparation of polymeric‐drug adducts. Also, similar monomeric phthalimides may be synthesised starting from a number of other hydroxy or amino acids, thus providing wider possibilities for the synthesis of pharmacologically active polymers.

The method for preparation of monomer is simple and the exchange reactions provide a simple and practical solution to prepare some classes of macromolecular drugs.

The method of preparation of polymers was novel and may be useful for preparation of polymeric‐drug adducts.

The purpose of this research paper is to investigate the changes in free volume by adding acrylate modified nanodiamond particles. In this study, a cross-linked thiol-ene (T) network was obtained under ultraviole light. The changes in free volume were analyzed when acrylate-modified nanodiamond (M-ND) particles were added to the nanocomposites obtained. Positron annihilation lifetime spectroscopy (PALS), a well-established method, was used for this analysis. In addition, the effect of nanocomposites containing different ratios of acrylate M-ND particles (1, 2, 3 and 5 Wt. %) on the surface and the thermal properties were also examined.

The impact of different quantities of acrylate M-ND on the free volume and surface morphological properties of thiol-ene polymer networks were studied by using scanning electron microscopy, differential scanning calorimetry, attenuated total reflection, Fourier transform infrared spectroscopy, PALS and thermogravimetric analysis measurements.

The thermal properties of T/M-ND were found to depend on the weight percentages of the M-ND content. For increasing weight percentages of M-ND added to thio-lene polymer networks, the glass transition temperature (T_g) increased from 103°C to 154°C. The ortho-positronium (o-Ps) lifetime (free volume) and free volume fraction characterization of T/M-ND nanocomposites were investigated using PALS. Increasing temperature caused both the o-Ps lifetime (free volume) to change with increasing saturation and to linearly increase the intensity; however, an increasing weight percentage of M-ND caused no change at all for the o-Ps lifetime (free volume) and the free volume fraction.

According to published literature, and to the best of the authors’ knowledge, this is the first time a study examining the free volume properties in a thiol-ene system has been carried out.

The purpose of this paper is to present a model that can be used to simulate the photopolymerization process in micro‐stereolithography (SL) in order to predict the shape of the cured parts. SL is an additive manufacturing process in which liquid photopolymer resin is cross‐linked and converted to solid with a UV laser light source. Traditional models of SL processes do not consider the complex chemical reactions and species transport occurring during photopolymerization and, hence, are incapable of accurately predicting resin curing behavior. The model presented in this paper attempts to bridge this knowledge gap.

The chemical reactions involved in the photopolymerization of acrylate‐based monomers were modeled as ordinary differential equations (ODE). This model incorporated the effect of oxygen inhibition and diffusion on the polymerization reaction. The model was simulated in COMSOL and verified with experiments conducted on a mask‐based micro‐SL system. Parametric studies were conducted to investigate the possibilities to improve the accuracy of the model for predicting the edge curvature.

The proposed model predicts well the effect of oxygen inhibition and diffusion on photopolymerization, and the model accurately predicts the cured part height when compared to experiments conducted on a mask‐based SL system. The simulated results also show the characteristic edge curvature as seen in experiments.

A triacrylate monomer was used in the experiments conducted, so results may be limited to acrylate monomers. Shrinkage was not considered when comparing cured part shapes to those predicted using COMSOL.

This paper presents a unique and a pioneering approach towards modeling of the photopolymerization reaction in micro‐SL process. This research furthers the development of patent pending film micro‐SL process which can be used for fabrication of custom micro‐optical components.