Monitoring of visible light photopolymerization of an epoxy/dimethacrylate hybrid system by Raman and near-infrared spectroscopies

Asmussen, Silvana Valeria; Schroeder, Walter F.; Dell'Erba, Ignacio Esteban; Vallo, Claudia Ines

doi:10.1016/j.polymertesting.2013.08.005

Cited by 15 publications

(11 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Since the amounts of vinyl ester groups is enhanced in MVEO‐3, the viscosity and network interlock effect increase dramatically resulting in reduction reaction rate for MVEO‐3. Similar results have been observed by HUA et al . that the epoxy network formation for SIN(Simultaneous Interpenetrating Networks) consisting of less amount of epoxy (epoxy/urethane acrylate resin=20/80) was suppressed even more seriously than those containing more epoxy(epoxy/UAR≥50/50).…”

Section: Resultssupporting

confidence: 89%

“…The total polymerization enthalpies for MVEO‐1, MVEO‐2 and MVEO‐3 are 312, 325, and 335 J/g, which are lower than the averages enthalpies calculated from corresponding ratios of TGDDM and MVER (409, 387, and 364, J/g respectively), suggesting that MVEOs were not fully cured. MVEOs are not be fully cured because of the cross‐linking of vinyl ester/St, which restrict the curing degree of epoxy/MeTHPA …”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Synthesis and curing behavior of novel multifunctional hybrid oligomers

Qian

Liu

Chen

et al. 2015

J of Applied Polymer Sci

View full text Add to dashboard Cite

Novel multifunctional hybrid vinylized epoxide oligomers (MVEOs) containing two different reactive groups were synthesized through the esterification of tetraglycidyl 4,4′‐diaminodiphenylmethane (TGDDM) with acrylic acid (AA) at various molar ratios. The changes of vinyl ester and epoxy groups in MVEOs were studied by Fourier Transform Infrared Spectroscopy, Nuclear Magnetic Resonance, and Gel permeation chromatograph. It was found that more amount of AA in the reactant would increase the contents of vinyl ester and molecular weight. The curing behavior of MVEOs has been studied by scanning differential scanning calorimetry (DSC). Two distinct exothermic peaks were observed in the MVEOs which can be attributed to the radical polymerization of vinyl ester/styrene and condensation polymerization of epoxy/MeTHPA, respectively. Two different kinds of curing programs have influenced each other which makes the exothermic peaks overlapped. The DSC scan of MVEO‐2 indicated that the radical initiated curing reaction of vinyl ester won't notably affect the curing of epoxy without MeTHPA. However, the thermal curing of vinyl ester in MVEO‐2 without MEKP/Co would be occurred with the temperature rising. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42276.

show abstract

Section: Resultssupporting

confidence: 89%

Section: Resultsmentioning

confidence: 99%

Synthesis and curing behavior of novel multifunctional hybrid oligomers

Qian

Liu

Chen

et al. 2015

J of Applied Polymer Sci

View full text Add to dashboard Cite

show abstract

“…This phenomenon must certainly be relevant when the Raman test is performed on or in the neighborhood of the Cu particles, but when the Raman measurement is performed on the epoxy matrix, the saturation is also observed, indicating that the incident radiation passes through of the matrix and ultimately reaches the copper surfaces. The strong fluorescence and the difficulty that this fluorescence involves in the epoxies are well-known [20]; for example, using a laser source with same wavelength of our work, cycloaliphatic epoxy could not be studied; however, the hybrid systems of epoxy-methacrylate were free from fluorescence [21]. Then, the response of the epoxy systems to different wavelength excitation measurements is complex.…”

Section: Raman Spectroscopy Preliminarymentioning

confidence: 88%

A micro-Raman study of Cu-particulate-filled epoxy matrix composites

Tognana¹,

Salgueiro²,

Valcarce³

2014

Express Polym. Lett.

View full text Add to dashboard Cite

Epoxy resins are used in structural applications ranging from high-performance composites for aerospace applications to encapsulants for the microelectronics industry because of their high thermal resistance, high tensile strength and modulus, and good chemical resistance. It is well known that the most important factors that influence their performance are the molecular architecture, the ratio between the epoxide and the hardener, and the cure conditions, frequently at a high temperature, which determine the final properties of the material. The influence of the filler particles on the curing is still a subject of study and clearly depends on the nature of the particles [1][2][3][4][5]. Epoxy matrix composites find new applications every day in several areas of engineering and technology. For example, copper-filled composites have a high possibility of being used in microelectronics because the high thermal conductivity of copper allows the composite to be a good heat dissipator, which serves as protection to electronic devices [6,7]. The matrix-particle interphases also play an important role. The physical properties of the polymeric composites can be significantly influenced by their thermal history; in fact, internal stresses are developed during the fabrication process and further thermal treatments. Abstract. A micro-Raman study is carried out to investigate the influence of the filler on the curing process of bisphenol A diglycidyl ether (DGEBA)-based epoxy matrix composites. The composites are cured (14 h at 393 K) with an anhydride (methyl tetrahydro phthalic anhydride, MTHPA, 100:90 pbw), catalyzed with a tertiary amine (0.7 pbw) and filled with a 30% volume of Cu particles of approximately 75 !m in diameter. The experimental results are compared with those obtained for the same epoxy resin unfilled and for the same composite with Cu filler but not catalyzed. The micro-Raman experimental technique is used to search for information on the curing process in different regions of the matrix, near to and far from the copper filler, taking into account the results of differential-scanning-calorimetry measurements performed on the same composites. The results provide information on the influence of the copper filler on the curing process of the epoxy matrix. Differences were observed in the peaks associated with the epoxy ring and the ester group as a function of the distance to the nearest copper particle, but no differences were observed between the different composites.

show abstract

“…Raman spectroscopy studies were performed at room temperature ( ca 20 °C) with an Invia Reflex confocal Raman microprobe (Renishaw). Details concerning this technique have been reported elsewhere . The conversions of CC double bonds and SH groups were calculated from the decay of the bands located at 1642 and 2575 cm −1 , respectively.…”

Section: Methodsmentioning

confidence: 99%

Novel hydrogels based on a high‐molar‐mass water‐soluble dimethacrylate monomer

Asmussen

Gómez

Vallo

2018

Polymer International

View full text Add to dashboard Cite

This report describes the preparation and swelling behaviour of novel hydrogels based on a water‐soluble dimethacrylate monomer (EBisEMA), which is characterized by a relatively high molar mass (Mn ∼ 1700 g mol−1) and contains a high proportion of aliphatic ether bonds in its structure. This feature results in moderately crosslinked and flexible polymer networks. Significant differences were observed in degree of swelling, depending on the synthesis method employed to obtain the hydrogels. The equilibrium water sorption of EBisEMA photopolymerized in bulk was 68 wt% while that of EBisEMA photopolymerized in aqueous solution (0.5 g mL−1) was 104 wt%. Thiol–methacrylate hydrogels were prepared by visible light photopolymerization of EBisEMA with a tetrafunctional thiol (PETMP) at various EBisEMA‐to‐PETMP molar ratios. These hydrogels contained unreacted thiol groups because of a faster homopolymerization reaction of EBisEMA. Hydrogels were also prepared in bulk by propylamine‐catalysed Michael addition reaction. No significant differences in swelling were observed between EBisEMA homopolymer and photocured EBisEMA–PETMP copolymer. Conversely, a marked increase in water uptake (110 wt%) was observed in the EBisEMA–PETMP hydrogels prepared by the Michael addition reaction catalysed by propylamine. These trends are explained in terms of a balance between the mass fraction of hydrophilic groups and the crosslinking density of the network. EBisEMA–PETMP hydrogels formulated with thiol in excess showed a noticeable tendency to adhere to diverse substrates, including paper, metals, glass and skin. This feature makes them especially attractive in applications for which adhesion is particularly critical such as dermatological patches. © 2018 Society of Chemical Industry

show abstract

Monitoring of visible light photopolymerization of an epoxy/dimethacrylate hybrid system by Raman and near-infrared spectroscopies

Cited by 15 publications

References 27 publications

Synthesis and curing behavior of novel multifunctional hybrid oligomers

Synthesis and curing behavior of novel multifunctional hybrid oligomers

A micro-Raman study of Cu-particulate-filled epoxy matrix composites

Novel hydrogels based on a high‐molar‐mass water‐soluble dimethacrylate monomer

Contact Info

Product

Resources

About