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The authors aimed to develop environmentally stable NIR‐absorbing windows by blending a near‐infrared (NIR)‐absorbing dye and a photo‐crosslinkable polymer.

To prepare an environmentally stable NIR‐absorbing window, a NIR‐absorbing dye was mixed with crosslinkable poly(vinyl cinnamate) (PVCn). The crosslinking of PVCn was carried out by photo‐dimerisation reaction of cinnamate with UV‐exposure at a wavelength of 254 nm for 4 min.

The resistance of the photo‐crosslinked hybrid films against humidity, heat, and ultraviolet radiation damage was improved dramatically relative to the pristine NIR‐absorbing dye. These improvements result from the protection of NIR‐absorbing dye to moisture exposure in the presence of the polymer network.

The simple and practical method resulted in a dramatic improvement in the environmental stability of NIR‐absorbing window.

Epoxy acrylate which is commercially utilized for UV curable coatings although has excellent adhesion, flexibility, hardness and chemical resistance, they lack in antimicrobial properties. Citric acid (CA) is economical as well as a bio-based compound which possess an antimicrobial activity. So, the purpose of this research investigation is the preparation of CA-based oligomer which can be further incorporated with epoxy acrylate and tri (propylene glycol) Diacrylate (TPGDA) to form uv curable coating and the study of its antimicrobial property.

A UV-curable unsaturated oligomer (CUV) was synthesized from CA and glycidyl methacrylate (GMA). The chemical structure of CUV was confirmed by FTIR, ¹H NMR, GPC, hydroxyl value, acid value and iodine value. Further, CUV was assimilated as an antimicrobial as well as crosslinking agent to copolymerize with epoxy acrylate oligomer and a series of UV-cured antimicrobial coatings were concocted by employing UV-curing machine. The consequence of varying the fraction of CUV on the mechanical, chemical, thermal and antimicrobial properties of UV-cured wood coatings was explored.

Results exhibited good mechanical, chemical and thermal properties. In addition, it was perceived that the zone of inhibition against S. aureus got enlarged with increasing content of CUV in the coating formulation.

The synthesized bio-based CUV reveals an extensive potential to ameliorate the antimicrobial properties of UV-curable coatings.

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.

Proposes to examine acceleration of photo‐oxidative degradation of high‐density polyethylene (HDPE) by using photosensitive acetophenone‐formaldehyde resin (AFR).

Degradation of HDPE by UV light was investigated in the presence of photosensitive AFR on natural weathering. The experiments were done at constant temperatures (40, 65 and 90°C). The results were determined by FT‐IR spectrophotometric and viscometric methods. Measurement of the rate of formation of carbonyl groups on the FT‐IR showed the evidence of degradation. The carbonyl indices of photo‐oxidation of HDPE with/without AFR were determined by FT‐IR spectroscopy. The molecular weights of the samples (M_η values) were measured by viscometry.

The amount of carbonyl present in the AFR containing HDPE samples and the changes in their molecular weights were found to depend on the irradiation period, temperature and amount of AFR in the mixture. The improvements in UV performance have been observed by using 1 per cent photosensitive AFR in the mixture. Photo‐oxidative degradation also appeared to be accelerated by heat.

This study can be focused on using photosensitive resins for the polymer degradations just as powder mixture, but the HDPE sample used did not contain antioxidants. From this point of view, commercial HDPE and AFR must be mixed as a film‐former and the AFR concentration will be higher than those of this work.

This work provides technical information for the application of photosensitive resins for easy degradation of HDPE packaging materials.

The method in which a photosensitive resin is used in the polymer degradation may be a reference for other relevant studies.

In recent years, electronic devices have increasingly employed printed circuits produced using electrically conductive adhesives, commonly known as polymer thick films. This method is much more cost‐effective and efficient than other methods of wiring, including those using chemical etching or plating. In the past, the use of metal‐filled polymers as conductors in printed circuit fabrication has suffered from several limitations such as poor solderability, conductivity and adhesion. A new electrically conductive metal‐filled polymer formulation has been developed which overcomes these problems inherent in typical polymer thick film inks. This new product is based on transient liquid‐phase sintering wherein the metallic components of the formulation sinter at a relatively low temperature, resulting in a highly conductive continuous metal network. The sintering is achieved through the interaction of several metallic components with an adhesive‐flux component. The final product is highly conductive, solderable and exhibits excellent adhesion to a wide range of substrate materials. A new process for manufacturing fine‐line printed circuit boards using this ink technology is under investigation. It promises potentially simpler processing and lower cost than plating. In this new process, traces (in the form of troughs in the dielectric) are imaged using conventional photoimageable dielectrics. Exposure and developing conditions depend upon the polymer system used. The transient liquid phase sinterable conductive ink is applied to fill the photo‐exposed conductor pattern. Next, another layer of photoimageable dielectric is applied over the traces and imaged with vias for interconnections with subsequent layers. The dielectric is then cured and the ink applied to fill the vias. These steps may be repeated several times to produce low‐profile fine‐line multilayer printed circuits. This process for producing multilayer circuits using conductive inks simplifies the manufacturing of printed circuits, reduces profile, eliminates most waste in manufacturing, and reduces cost compared with plating.

Applies FT‐IR spectroscopic techniques to study the degradative process occurring on ageing/UV irradiation of lac resin. Unequivocally concludes that hydroperoxidation and inter‐etherification reactions are more likely to occur during the degradative process. MS(FAB) and solubility studies also support FT‐IR studies. Establishes that lac resin is remarkably stable to long wavelength UV radiation but tends to undergo prominent degradation on exposure to short wavelength UV irradiation.

UV curable systems have found wide applications in clear coatings. However, coatings containing pigment showed a degree of curing inhibition due to the absorption, scattering and reflection of the UV radiation caused by the presence of pigments in the coating film. This results in poor through‐cure and consequently in poor adhesion. Thus, pigments used in the UV curable coating systems should not absorb radiation in the same region as the photo‐initiators. One of the solutions to such a problem, reported in this paper, was to develop more reactive, alcohol soluble, non‐heat reactive, low molecular weight cresol based, pigmented novolac epoxy acrylate systems, which have a lower absorption in the UV region. In addition, the effects of several photoinitiators having absorption in the longer wavelength region of the UV spectrum were investigated.

This paper aims to review the advances in additive manufactured (AM) scaffolds for bone tissue engineering (TE). A discussion on the state of the art and future trends of bone TE scaffolds have been done in terms of design, material and different AM technologies.

Different structural features and materials used for bone TE scaffolds are evaluated along with the discussion on the potential and limitations of different AM scaffolds. The latest research to improve the biocompatibility of the AM scaffolds is also discussed.

The discussion gives a clear understanding on the recent research trend in bone TE AM scaffolds.

The information available here would be useful for the researchers working on AM scaffolds to get a quick overview on the recent research trends and/or future direction to work on AM bone TE scaffolds.

This paper presents a new indirect scaffold fabrication method for soft tissue based on rapid prototyping (RP) technique and preliminary characterization for collagen scaffolds.

This paper introduces the processing steps for indirect scaffold fabrication based on the inkjet printing technology. The scaffold morphology was characterized by scanning electron microscopy. The designs of the scaffolds are presented and discussed.

Theoretical studies on the inkjet printing process are presented. Previous research showed that the availability of biomaterial that can be processed on a commercial RP system is very limited. This is due mainly to the unfavorable machine processing parameters such as high working temperature and restrictions on the form of raw material input. The process described in this paper overcomes these problems while retaining the strength of RP techniques. Technical challenges of the process are presented as well.

Harnessing the ability of RP techniques to control the internal morphology of the scaffold, it is possible to couple the design of the scaffold with controlled cell‐culture condition to modulate the behavior of the cells. However, this is just initial work, further development will be needed.

This method enables the designer to manipulate the scaffold at three different length scales, namely the macroscopic scale, intermediate scale and the cellular scale.

The work presented in this paper focuses on important processing steps for indirect scaffold fabrication using thermal‐sensitive natural biomaterial. A mathematical model is proposed to estimate the height of a printed line.

The purpose of this paper is the design and investigation of novel acrylated epoxidized soybean oil-based photocurable systems as candidate materials for optical 3D printing.

Aromatic dithiols, benzene-1,3-dithiol or benzene-1,4-dithiol, were used as cross-linking agents of acrylated epoxidized soybean oil in these systems. Kinetics of photocross-linking was investigated by real-time photorheometry using two different photoinitiators, 2, 2-dimethoxy-2-phenylacetophenone or 2-hydroxy-2-methylpropiophenone, in different quantities. The effect of the initial composition on the rate of photocross-linking, mechanical, thermal properties and swelling of obtained polymers was investigated.

The rate of photocross-linking was higher, more cross-links and shorter polymer chains between cross-linking points of the network were formed when benzene-1,4-dithiol and 2, 2-dimethoxy-2-phenylacetophenone were used in compositions. The higher yield of insoluble fraction, glass transition temperatures and values of compressive modulus were obtained when benzene-1,3-dithiol and 2, 2-dimethoxy-2-phenylacetophenone were used in compositions.

This is the first study of acrylated epoxidized soybean oil-based thiol-ene system by real-time photorheometry. The designed novel photocurable systems based on acrylated epoxidized soybean oil and benzenedithiols are promising renewable photoresins for rapid optical 3D printing on demand.