scholarly journals Raman Spectroscopic Characterization of Polymerization Kinetics of Cyanoacrylate Embolic Glues for Vascular Embolization

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3362
Author(s):  
Yongjiang Li ◽  
Lei Xiao ◽  
Zian Wang ◽  
Kejie Chen ◽  
Chundong Xue ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Polymerization Kinetics ◽  
Polymerization Rate ◽  
Polymerization Process ◽  
Slow Phase ◽  
Invasive Technique ◽  
Iodized Oil ◽  
Essential Information ◽  
Kinetics Of

Endovascular glue embolization is a minimally invasive technique used to selectively reduce or block the blood supply to specific targeted vessels. Cyanoacrylate glues, mixed with radiopaque iodized oil, have been widely used for vascular embolization owing to their rapid polymerization rate, good penetration ability and low tissue toxicity. Nevertheless, in clinical practice, the selection of the glue–oil proportion and the manual injection process of mixtures are mostly based on empirical knowledge of operators, as the crucial physicochemical effect of polymerization kinetics has rarely been quantitatively investigated. In this study, the Raman spectroscopy is used for studying the polymerization kinetics of n-butyl-cyanoacrylate-based glues mixed with an iodized oil. To simulate the polymerization process during embolization, glue–oil mixtures upon contact with a protein ionic solution mimicking blood plasma are manually constructed and their polymerization kinetics are systematically characterized by Raman spectroscopy. The results demonstrate the feasibility of Raman spectroscopy in the characterization of polymerization kinetics of cyanoacrylate-based embolic glues. The polymerization process of cyanoacrylate-based mixtures consists of a fast polymerization phase followed by a slow phase. The propagation velocity and polymerization time primarily depend on the glue concentrations. The commonly used 50% mixture polymerizes 1 mm over ∼21.8 s, while it takes ∼51 min to extend to 5 mm. The results provide essential information for interventional radiologists to help them understand the polymerization kinetics of embolic glues and thus regulate the polymerization rate for effective embolization.

The effect of electrondonors on the polymerization kinetics of isoprene

1980 ◽  
Vol 45 (12) ◽  
pp. 3338-3346
Author(s):  
Miroslav Kašpar ◽  
Jiří Trekoval
Keyword(s):  
Induction Period ◽  
Ethyl Ether ◽  
Reaction Order ◽  
Propagation Rate ◽  
Reaction Scheme ◽  
Polymerization Kinetics ◽  
Polymerization Rate ◽  
Constant Concentration ◽  
Initial Concentration ◽  
Kinetics Of

The effect of small additions of 1-octene, butyl ethyl ether and triethylamine on the polymerization kinetics of isoprene (2-methyl-1,3-butadiene) in benzene initiated with butyllithium was investigated by employing the GLC analysis. The addition of 1-octane was reflected only in a shorter induction period of the reaction; the effect on the propagation rate was insignificant. With the increasing amount of butyl ethyl ether, the polymerization rate increases linearly, while the reaction order with respect to the concentration of triethylamine is variable and increases from 0.33 to 0.66 with the increasing concentration of the initiator. For a constant concentration of triethylamine, the reaction order with respect to the initial concentration of the initiator was found to vary considerably, reaching even negative values. A reaction scheme was suggested, taking into account the competition between two different solvates of alkyllithium.

scholarly journals Synthesis and Polymerization Kinetics of Rigid Tricyanate Ester

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1686
Author(s):  
Andrey Galukhin ◽  
Roman Nosov ◽  
Ilya Nikolaev ◽  
Elena Melnikova ◽  
Daut Islamov ◽  
...  
Keyword(s):  
Kinetic Analysis ◽  
Single Step ◽  
Polymerization Kinetics ◽  
Scanning Calorimetry ◽  
Modulated Differential Scanning Calorimetry ◽  
Diffusion Controlled ◽  
Polymerization Product ◽  
The One ◽  
Kinetics Of

A new rigid tricyanate ester consisting of seven conjugated aromatic units is synthesized, and its structure is confirmed by X-ray analysis. This ester undergoes thermally stimulated polymerization in a liquid state. Conventional and temperature-modulated differential scanning calorimetry techniques are employed to study the polymerization kinetics. A transition of polymerization from a kinetic- to a diffusion-controlled regime is detected. Kinetic analysis is performed by combining isoconversional and model-based computations. It demonstrates that polymerization in the kinetically controlled regime of the present monomer can be described as a quasi-single-step, auto-catalytic, process. The diffusion contribution is parameterized by the Fournier model. Kinetic analysis is complemented by characterization of thermal properties of the corresponding polymerization product by means of thermogravimetric and thermomechanical analyses. Overall, the obtained experimental results are consistent with our hypothesis about the relation between the rigidity and functionality of the cyanate ester monomer, on the one hand, and its reactivity and glass transition temperature of the corresponding polymer, on the other hand.

scholarly journals Chemometrics-Assisted Raman Spectroscopy Characterization of Tunable Polymer-Peptide Hybrids for Dental Tissue Repair

2021 ◽  
Vol 8 ◽  
Author(s):  
Paulette Spencer ◽  
Qiang Ye ◽  
Nilan J. B. Kamathewatta ◽  
Sarah K. Woolfolk ◽  
Brenda S. Bohaty ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Chemical Characterization ◽  
Heterogeneous Material ◽  
Relevant Information ◽  
Biological Tissues ◽  
Dental Tissue ◽  
Material Interfaces ◽  
Essential Information ◽  
Tissue Interfaces

The interfaces that biological tissues form with biomaterials are invariably defective and frequently the location where failure initiates. Characterizing the phenomena that lead to failure is confounded by several factors including heterogeneous material/tissue interfaces. To seamlessly analyze across these diverse structures presents a wealth of analytical challenges. This study aims to develop a molecular-level understanding of a peptide-functionalized adhesive/collagen hybrid biomaterial using Raman spectroscopy combined with chemometrics approach. An engineered hydroxyapatite-binding peptide (HABP) was copolymerized in dentin adhesive and dentin was demineralized to provide collagen matrices that were partially infiltrated with the peptide-functionalized adhesive. Partial infiltration led to pockets of exposed collagen—a condition that simulates defects in adhesive/dentin interfaces. The spectroscopic results indicate that co-polymerizable HABP tethered to the adhesive promoted remineralization of the defects. The spatial distribution of collagen, adhesive, and mineral as well as crystallinity of the mineral across this heterogeneous material/tissue interface was determined using micro-Raman spectroscopy combined with chemometrics approach. The success of this combined approach in the characterization of material/tissue interfaces stems from its ability to extract quality parameters that are related to the essential and relevant portions of the spectral data, after filtering out noise and non-relevant information. This ability is critical when it is not possible to separate components for analysis such as investigations focused on, in situ chemical characterization of interfaces. Extracting essential information from complex bio/material interfaces using data driven approaches will improve our understanding of heterogeneous material/tissue interfaces. This understanding will allow us to identify key parameters within the interfacial micro-environment that should be harnessed to develop durable biomaterials.

scholarly journals Raman spectroscopy for the characterization of the polymerization rate in an acrylamide-based photopolymer

2008 ◽  
Vol 47 (2) ◽  
pp. 206 ◽  
Author(s):  
Raghavendra Jallapuram ◽  
Izabela Naydenova ◽  
Hugh J. Byrne ◽  
Suzanne Martin ◽  
Robert Howard ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Polymerization Rate

Characterization of carotenoids in soil bacteria and investigation of their photodegradation by UVA radiation via resonance Raman spectroscopy

The Analyst ◽  
2015 ◽  
Vol 140 (13) ◽  
pp. 4584-4593 ◽  
Author(s):  
Vinay Kumar B. N. ◽  
Bernd Kampe ◽  
Petra Rösch ◽  
Jürgen Popp
Keyword(s):  
Raman Spectroscopy ◽  
Soil Bacteria ◽  
Resonance Raman Spectroscopy ◽  
Resonance Raman ◽  
Kinetics Of ◽  
Uva Radiation

Analysis of the photodegradation kinetics of pigments in soil bacteria for better characterization of carotenoidsviaresonance Raman spectroscopy is described.

scholarly journals Thermal and Mechanical Characterization of EMA-TEGDMA Mixtures for Cosmetic Applications

2018 ◽  
Author(s):  
Ruben Donoso ◽  
José Antonio Reina ◽  
Marta Giamberini ◽  
Silvia De La Flor ◽  
Francesc Ferrando ◽  
...  
Keyword(s):  
Triethylene Glycol ◽  
Polymerization Rate ◽  
Solid Component ◽  
Polymerization Process ◽  
Liquid Component ◽  
Triethylene Glycol Dimethacrylate ◽  
Ethyl Methacrylate ◽  
Methacrylate Monomers ◽  
Methacrylic Monomers

Mixtures of methacrylic polymers are the most common materials for making composites to be used as resins for dental and cosmetic applications. Some of these mixtures are composed by poly (ethyl methacrylate) (PEMA) and poly (methyl methacrylate) (PMMA), which constitute a solid component to be mixed with a liquid component made out of methacrylate monomers. The reaction between the thermal initiator benzoyl peroxyde (BPO) present in the solid component and the activator of the polymerization process, N,N-dimethyl-p-toluidine (DMT) present in the liquid component, gives rise to thermoset materials. In the present study, different liquid formulations composed by a mixture of two methacrylic monomers, ethyl methacrylate (EMA) and triethylene glycol dimethacrylate (TEGDMA) for cosmetic applications, were prepared and characterized, using a commercial powder (POW) composed by PEMA and PMMA. With the aim of improving workability during final application of the material, it was necessary to slow down the polymerization rate of liquid formulations. Their thermal behaviour was investigated by DSC in order to check the polymerization rate. Thermal stability of final materials was determined by TGA. DMTA, microindentation hardness and impact tests were performed on final materials, to assess their performance with respect to standard formulation. The combination of thermal and mechanical properties allows choosing which formulations could be suitable for use in cosmetics.

Polymerization of Enbucrilate/Lipiodol Mixtures In Vivo

2000 ◽  
Author(s):  
Matthew J. Gounis ◽  
Baruch B. Lieber ◽  
L. Nelson Hopkins
Keyword(s):  
High Speed ◽  
Polymerization Kinetics ◽  
Polymerization Process ◽  
Embolic Agent ◽  
Model Parameters ◽  
Normal Brain ◽  
Normal Density ◽  
Precise Knowledge ◽  
Kinetics Of

Abstract Embolization is an endovascular procedure used to treat cerebral arteriovenous malformations (AVMs). AVMs are pathological shunts between arteries and veins, which bypass normal brain structures. An embolic agent commonly used to occlude AVMs is n-butyl 2-cyanoacrylate (NBCA). Although NBCA has shown to be efficacious for this application, precise knowledge of its polymerization process in vivo is needed. Inadvertent occlusion of arterial feeders proximal to the AVM nidus will occur when polymerization of NBCA is too rapid. This may lead to revascularization of the AVM. Conversely, long polymerization times may result in the occlusion of draining veins, with subsequent brain hemorrhage and pulmonary emboli. It is therefore critical to understand the kinetics of the polymerization process to obtain a complete glue cast of the arteriovenous transition (nidus) thus, yielding safe obliteration of the AVM. In order to elucidate the polymerization kinetics of NBCA, we examined the embolization process in the femoral and subclavian arteries of the rabbit. Various embolic agents composed of NBCA/lipiodol mixtures with and without the addition of glacial acetic acid (GAA) were injected. Blood flow through the femoral and subclavian arteries was measured prior to and during embolization. All studies were recorded with high-speed digital subtraction angiography (DSA). Preliminary analysis of the data suggests that flow decay during embolization exhibits a behavior that can be modeled via a lagged-normal density curve. Optimized model parameters vis a vis the experimental data are related to the polymerization kinetics. These parameters can be used to form a quantitative basis of comparison for the various liquid embolic mixtures.

Polymerization Kinetics of Methacrylic Groups in Organic-Inorganic Hybrid Polymeric Thin Films

2007 ◽  
Vol 1007 ◽  
Author(s):  
Congji Zha ◽  
Xinshi Luo ◽  
Barry Luther-Davies
Keyword(s):  
Thin Films ◽  
Thermal Treatment ◽  
Spectroscopic Technique ◽  
Polymerization Kinetics ◽  
Polymerization Process ◽  
Thermal Curing ◽  
Polymeric Thin Films ◽  
Ft Ir ◽  
Ir Spectroscopic ◽  
Kinetics Of

ABSTRACTIn this paper, the polymerization kinetics of unsaturated double bonds (C=C) in TiO2- and ZrO2-doped hybrid polymeric thin films during UV irradiation and thermal curing is studied by monitoring the variation of C=C absorption band at 1630 cm-1 using FT-IR spectroscopic technique. Experimental results showed that polymerization of the unsaturated C=C groups in the TiO2- and ZrO2-doped hybrid polymers can be realized by either photo-irradiation or thermal treatment. The UV-induced polymerization process is much faster than thermal curing, but a full conversion of C=C groups into polyacrylate chains cannot be achieved without thermal treatment. The catalytic effect of TiO2 and ZrO2 on promoting the polymerization of C=C groups was observed, and the time of UV exposure and thermal curing for cross-linking C=C bonds was found to decrease with the increase of the concentration of TiO2 and ZrO2. The activation energy of the hybrid material containing varied concentration of TiO2 and ZrO2 was calculated, and the results indicated that TiO2 is more active than ZrO2 in promoting the polymerization of the unsaturated C=C bonds. Finally, the mechanisms for TiO2 and ZrO2 enhancing the material's photosensitivity (i.e. promoting polymerization of C=C bonds) have been proposed and discussed.

Polymerization kinetics of indene, methyl methacrylate and acrylonitrile and characterization of their terpolymer

2009 ◽  
Vol 16 (6) ◽  
pp. 693-702 ◽  
Author(s):  
Hala F. Naguib ◽  
Samia M. Mokhtar ◽  
Nesren Z. Khalil ◽  
Maher Z. Elsabee
Keyword(s):  
Methyl Methacrylate ◽  
Polymerization Kinetics ◽  
Kinetics Of
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