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Article
Publication date: 19 March 2024

Diana Irinel Baila, Filippo Sanfilippo, Tom Savu, Filip Górski, Ionut Cristian Radu, Catalin Zaharia, Constantina Anca Parau, Martin Zelenay and Pacurar Razvan

The development of new advanced materials, such as photopolymerizable resins for use in stereolithography (SLA) and Ti6Al4V manufacture via selective laser melting (SLM…

Abstract

Purpose

The development of new advanced materials, such as photopolymerizable resins for use in stereolithography (SLA) and Ti6Al4V manufacture via selective laser melting (SLM) processes, have gained significant attention in recent years. Their accuracy, multi-material capability and application in novel fields, such as implantology, biomedical, aviation and energy industries, underscore the growing importance of these materials. The purpose of this study is oriented toward the application of new advanced materials in stent manufacturing realized by 3D printing technologies.

Design/methodology/approach

The methodology for designing personalized medical devices, implies computed tomography (CT) or magnetic resonance (MR) techniques. By realizing segmentation, reverse engineering and deriving a 3D model of a blood vessel, a subsequent stent design is achieved. The tessellation process and 3D printing methods can then be used to produce these parts. In this context, the SLA technology, in close correlation with the new types of developed resins, has brought significant evolution, as demonstrated through the analyses that are realized in the research presented in this study. This study undertakes a comprehensive approach, establishing experimentally the characteristics of two new types of photopolymerizable resins (both undoped and doped with micro-ceramic powders), remarking their great accuracy for 3D modeling in die-casting techniques, especially in the production process of customized stents.

Findings

A series of analyses were conducted, including scanning electron microscopy, energy-dispersive X-ray spectroscopy, mapping and roughness tests. Additionally, the structural integrity and molecular bonding of these resins were assessed by Fourier-transform infrared spectroscopy–attenuated total reflectance analysis. The research also explored the possibilities of using metallic alloys for producing the stents, comparing the direct manufacturing methods of stents’ struts by SLM technology using Ti6Al4V with stent models made from photopolymerizable resins using SLA. Furthermore, computer-aided engineering (CAE) simulations for two different stent struts were carried out, providing insights into the potential of using these materials and methods for realizing the production of stents.

Originality/value

This study covers advancements in materials and additive manufacturing methods but also approaches the use of CAE analysis, introducing in this way novel elements to the domain of customized stent manufacturing. The emerging applications of these resins, along with metallic alloys and 3D printing technologies, have brought significant contributions to the biomedical domain, as emphasized in this study. This study concludes by highlighting the current challenges and future research directions in the use of photopolymerizable resins and biocompatible metallic alloys, while also emphasizing the integration of artificial intelligence in the design process of customized stents by taking into consideration the 3D printing technologies that are used for producing these stents.

Details

Rapid Prototyping Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 7 March 2016

Zhishi Li, Huajin Wang, Sheng Zhang, Wei Zhao, Qinghuai Jiang, Mingqiang Wang, Jun Zhao and Wei Lu

– This paper aims to discuss how acrylic resin influences the smoke generation of intumescent flame retardant coatings.

Abstract

Purpose

This paper aims to discuss how acrylic resin influences the smoke generation of intumescent flame retardant coatings.

Design/methodology/approach

Thermal decomposition kinetics is used in this study to simulate the burning process. The thermal decomposition of acrylic resin can be identified in the intumescent coatings through the multi-peak fitting of derivative thermogravimetric (DTG) curves. The dormant influence of acrylic resin, combined with the smoke density, is calculated.

Findings

Multiple peaks fitting method of DTG curves helps estimate the decomposition process of acrylic resin in flame retardant coating. Combining DTG data with the smoking curve, smoking generation of acrylic resin during the combustion could be evaluated. The decomposition conversion rate of acrylic resin is 21.13 per cent. Acrylic resin generates 34.64 per cent of the total amount of smoke produced during the combustion of intumescent flame retardant coatings.

Research limitations/implications

All the other intumescent flame retardant coating systems could be studied using the same approach as that used in this work to achieve an improved understanding of the smoke generation process during combustion.

Practical implications

The method developed here provided a simple and practical solution to analyse the decomposition and smoking generation of acrylic resin in the coating mixtures. It also can be used to analyse any thermal decomposition process of any mixed compounds.

Originality/value

The analysis method to evaluate resin’s smoking generation of coating’s total generation is novel, and it could be applied in all kinds of coatings and mixtures to estimate the smoking generation of one composition.

Details

Pigment & Resin Technology, vol. 45 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 September 1995

K. Renap and J.P. Kruth

Most stereolithography systems use a blade to accomplish the recoating of the part being built with a new layer of resin. States the problems associated with this technique and…

1343

Abstract

Most stereolithography systems use a blade to accomplish the recoating of the part being built with a new layer of resin. States the problems associated with this technique and describes experiments conducted to determine how recoating parameters should be controlled. Differentiates between recoating over an entirely solid substrate and over one consisting of solid and liquid, i.e. the “trapped volume” condition. Discusses parameter control for both of these conditions. Concludes that recoating is an important part of the stereolithography process which must be optimized to ensure accuracy of prototype parts.

Details

Rapid Prototyping Journal, vol. 1 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 1 December 1998

Hans Mayer

An introduction to the topic of aqueous silicone resin coating systems for exterior masonry. Concentrates on applications in the construction industry.

1587

Abstract

An introduction to the topic of aqueous silicone resin coating systems for exterior masonry. Concentrates on applications in the construction industry.

Details

Pigment & Resin Technology, vol. 27 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 December 1999

O. Akaranta and A.O. Aloko

Copolymer resins of peanut skin tannin extract, aldehydes and cashew nut shell liquid were prepared. The resins were blended with bitumen and used in formulating oleoresinous wood…

402

Abstract

Copolymer resins of peanut skin tannin extract, aldehydes and cashew nut shell liquid were prepared. The resins were blended with bitumen and used in formulating oleoresinous wood varnishes. The film properties of the varnishes were determined and the results showed that the gloss and scratch hardness of the films increased with increase in the quantity of cashew nut shell liquid/tannin‐aldehyde resins incorporated. The results also showed that the resins improved the chemical resistance of the varnish films. Varnish compositions containing 50:50 of bitumen and the resins gave films with satisfactory physical and chemical properties. The study showed that it is possible to formulate excellent oleoresinous wood varnishes using blends of bitumen and cashew nut shell liquid/tannin‐aldehyde resins.

Details

Pigment & Resin Technology, vol. 28 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 7 November 2008

W.B. Liu, J. Wang, Q.H. Qiu and M.L. Zhang

The paper's purpose is to optimise lab‐size synthesis process of a fluorene‐containing epoxy resin, characterise structure of the resulting epoxy resin and evaluate mechanical…

1567

Abstract

Purpose

The paper's purpose is to optimise lab‐size synthesis process of a fluorene‐containing epoxy resin, characterise structure of the resulting epoxy resin and evaluate mechanical properties of the cured fluorene‐containing polymers.

Design/methodology/approach

The synthesis of the fluorene‐containing epoxy resin was accomplished by the polycondensation of 9,9‐bis(4‐hydroxyphenyl)‐fluorene and epichlorohydrin in the presence of quaternary ammonium salt and composite solvent under vacuum. The chemical structure of epoxy resin thus obtained was characterised with FTIR, NMR and MS. The shear strengthes of cured fluorene‐containing epoxy resin were determined and compared with that of cured E‐44 bisphenol A epoxy resin and F‐44 novolac epoxy.

Findings

The epoxide equivalent weight (EEW) of the fluorene‐containing epoxy resin reached 240‐246 g/mol under optimal epoxidising condition. The resulting epoxy resin exhibited approximate high temperature performance relative to F‐44 novolac epoxy, much better heat resistance than that of E‐44 epoxy resin and lower moisture uptake than that of the two above‐described resins.

Research limitations/implications

The shear strength of cured fluorene‐containing epoxy resin was relatively low at ambient temperature, whereas was much higher than that of bisphenol A epoxy resin at higher temperature, making it a potential candidate for many applications such as high temperature adhesives, coatings and matrix resins for advanced composite.

Originality/value

The method for preparation was modified and improved, structure characterisation was comprehensive. The material prepared could find numerous applications as heat‐resistant adhesives and matrix resins.

Details

Pigment & Resin Technology, vol. 37 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 6 July 2015

Lijun Chen, Zhongbin Bao, Zhengrong Fu and Wen Li

The purpose of this research is to prepare a dispersion resin with good dispersity and a colour paste with good stability. At present, the colour paste is being prepared using the…

Abstract

Purpose

The purpose of this research is to prepare a dispersion resin with good dispersity and a colour paste with good stability. At present, the colour paste is being prepared using the pigment dispersion resin which has the group quaternary ammonium. The dispersion resin prepared has good dispersity of pigment and extender. However, the stability of storage and construction of the colour paste is relatively poor, which has a negative influence on the application of cathodic electrodeposited (CED) coatings. However, the detailed investigation on the dispersion resin and the stable colour paste has not been reported.

Design/methodology/approach

Three steps are adopted to prepare the dispersion resin, that is blocking toluene diisocyanate (TDI), quaternary ammoniation of blocked TDI and ring opening of epoxy resin. The resultant dispersion is used to prepare the colour paste. The factors, which have an influence on the dispersity of the dispersion resin and stability of the colour paste, are optimised.

Findings

The typical recipes of preparing the dispersion resin and the resultant colour paste are obtained. The dispersity of the dispersion resin and stability of the colour paste are good based on the typical recipe. In addition, the film of the CED coating is smooth, dense and hard when the colour paste is used in the CED coating.

Practical implications

The dispersion resin can be used to prepare a colour paste, which can be used in the CED coatings. In addition, it also can be applied as a binder of coatings and adhesions.

Originality/value

The factors, which have an influence on the dispersity of the dispersion resin and stability of the colour paste, are studied in detail. The typical recipes of preparing the dispersion resin and the resultant colour paste are obtained. Based on the typical recipe, the dispersity of the dispersion resin and stability of the colour paste are good.

Details

Pigment & Resin Technology, vol. 44 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 May 1990

S. Swamp

The X‐ray diffraction patterns of epoxy resins: four samples with different epoxide equivalents and coal‐tar blended epoxy resins: three samples with different epoxide equivalents…

Abstract

The X‐ray diffraction patterns of epoxy resins: four samples with different epoxide equivalents and coal‐tar blended epoxy resins: three samples with different epoxide equivalents were recorded using CuKa X‐ray radiation. These X‐ray diffraction patterns were indicating the amorphous nature of the resins. Their intensity curves were subjected to Fourier Analysis for the first time in order to get more information about the difference between epoxy and coal‐tar blended epoxy resins in terms of their internal structure such as particle size, percentage crystallanity and electron density fluctuations. Also, the effect of different epoxide equivalent on these physical parameters was interpreted successfully in epoxy as well as coal‐tar blended epoxy resins.

Details

Pigment & Resin Technology, vol. 19 no. 5
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 1 February 1986

W. Schiffer

This paper is a critical comparison of the currently used methods to test prepregs which do not describe to a sufficient extent the flow behaviour of a prepreg resin during the…

Abstract

This paper is a critical comparison of the currently used methods to test prepregs which do not describe to a sufficient extent the flow behaviour of a prepreg resin during the pressing process. The new test method introduced herein is a characterisation of the viscosity of the resin melt. International standardisation of this test method is recommended.

Details

Circuit World, vol. 12 no. 3
Type: Research Article
ISSN: 0305-6120

Article
Publication date: 1 April 2005

Vipin Shukla, Ravi Shukla, Dharmendra Singh, Mahendra Singh, Madhu Bajpai and Sunita Seth

To prepare modified epoxy resins from resorcinol, cresol and phenol for improved adhesion and chemical resistance. To evaluate the properties of such modified epoxy resins.

Abstract

Purpose

To prepare modified epoxy resins from resorcinol, cresol and phenol for improved adhesion and chemical resistance. To evaluate the properties of such modified epoxy resins.

Design/methodology/approach

Epoxy novolac resins (ENRs) were synthesised by condensing epichlorohydrin with novolacs based on different types of substituted phenols for improving adhesion and chemical resistance. Various compositions were made by incorporating different proportions of polyamide resin. The chemical and adhesive strengths of the conventional epoxy and the modified epoxy resins were characterised.

Findings

The modified ENR using substituted phenols showed significant enhancement of chemical and adhesive strengths over the conventional DGEBA resin. The modified ENR had an increased number of glycidyl groups (thus increased functionality) of resin, which was responsible for improved chemical and adhesive strengths over the conventional DGEBA resin.

Research limitations/implications

The EPN resins used in the present context was synthesised from phenol, resorcinol and cresol and cured by polyamide resin of different amine values. Besides, it could be synthesised from phenolphthalein p‐aminophenol and p‐ter‐butylcatachol, etc.

Practical implications

The method developed provided a simple and practical solution to improving the adhesive and chemical resistance of cured epoxy phenol novolac resins.

Originality/value

The method for enhanced adhesive and chemical resistance of cured epoxy was novel and could find numerous applications in surface coating and adhesive.

Details

Pigment & Resin Technology, vol. 34 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

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