Determination of residual monomers resulting from the chemical polymerization process of dental materials

2013 ◽  
Author(s):  
S. Boboia ◽  
M. Moldovan ◽  
I. Ardelean
Keyword(s):  
Dental Materials ◽  
Polymerization Process ◽  
Chemical Polymerization

ANALYSIS OF WORK ON NANOSTRUCTURED MATERIALS IN ORTHOPEDIC DENTISTRY UNDER THE DIRECTION OF PROFESSOR E.S. KALIVRADZHIYAN

2020 ◽  
pp. 8-13
Author(s):  
Жанна Владимировна Вечеркина ◽  
Наталия Владимировна Чиркова ◽  
Михаил Анатольевич Крючков ◽  
Виктор Сергеевич Калиниченко
Keyword(s):  
Nanostructured Materials ◽  
Dental Materials ◽  
Physical And Mechanical Properties ◽  
High Strength ◽  
Barrier Properties ◽  
Working Time ◽  
Polymerization Process ◽  
High Tech ◽  
Acrylic Polymer ◽  
Removable Plate

Развитие технологий, основанных на использовании низкотоксичных материалов, позволит в скором будущем начать их применение в медицине. Применение наночастиц серебра, меди, кремния, цинка, титана, кобальта в качестве модифицирующей добавки позволит оказать активное влияние на структуру исходных материалов и изменение их свойств, а именно улучшение физико-механических, физико-химических и токсико-гигиенических свойств материалов. Наноразмерные частицы кремния, введенные в фиксирующие стоматологические материалы, приводят к улучшению физико-химических, физико-механических свойств кристаллизующихся материалов, а малая теплопроводность кремния может увеличить его рабочее время и снизить выделение тепла при реакции кристаллизации. Так как от этих характеристик зависит объем манипуляций, при фиксации ортопедических конструкций на опорных зубах целесообразно было бы привести рабочее время твердения к чистому времени твердения, что позволит увеличить объем манипуляций приготовленной массой без ухудшения ее свойств. Разработка высокопрочных, биосовместимых, высокотехнологичных нанопластмасс для базисов съемных пластиночных протезов является актуальной проблемой повышения качества жизни пациентов. Модификация наноразмерными частицами серебра, кремния акрилового полимера позволит улучшить такие физико-механические свойства, как ударную вязкость, прочность, температуростойкость, барьерные свойства, уменьшить усадку полимера на этапе полимеризации, в отличие от уже известных отечественных и дорогостоящих импортных полимеров. Наноразмерные частицы кремния, серебра являются сокатализаторами метилметакрилата, влияющими на уменьшение количества остаточного мономера после процесса полимеризации, тем самым повышая санитарно-химические и токсико-гигиенические характеристики полимера. Все вышеизложенное позволило сформулировать цель исследований по наноструктурированным материалам под руководством профессора …посвящается памяти профессора, д.м.н. Каливраджияна Э.С. The development of technologies based on the use of low-toxic materials will make it possible to begin their application in medicine in the near future. The use of nanoparticles of silver, copper, silicon, zinc, titanium, cobalt as a modifying additive will make it possible to actively influence the structure of the starting materials and change their properties, namely, improve the physicomechanical, physicochemical and toxicohygienic properties of materials. Nanosized silicon particles introduced into fixing dental materials lead to an improvement in the physicochemical, physicomechanical properties of crystallizing materials, and the low thermal conductivity of silicon can increase its working time and reduce heat generation during the crystallization reaction. Since the volume of manipulations depends on these characteristics, when fixing orthopedic structures on abutment teeth, it would be advisable to bring the working time of hardening to a pure hardening time, which will increase the volume of manipulations with the prepared mass without deteriorating its properties. The development of high-strength, biocompatible, high-tech nanoplastics for the bases of removable plate prostheses is an urgent problem to improve the quality of life of patients. Modification of acrylic polymer with nano-sized particles of silver and silicon will improve such physical and mechanical properties as impact strength, strength, temperature resistance, barrier properties, and reduce polymer shrinkage at the stage of polymerization, in contrast to the already known domestic and expensive imported polymers. Nanosized particles of silicon, silver are cocatalysts of methyl methacrylate, affecting the reduction of the amount of residual monomer after the polymerization process, thereby increasing the sanitary-chemical and toxic-hygienic characteristics of the polymer. All of the above made it possible to formulate the goal of research on nanostructured materials under the guidance of the professor …dedicated to the memory of the professor, d.m.s. Kalivrajiyan E.S.

UV Activated Copolymerization Coatings of Urethane Acrylates for Use in the Cosmetic Industry

2021 ◽  
Author(s):  
◽  
Zane Grigale-Soročina
Keyword(s):  
Color Constancy ◽  
Surface Hardness ◽  
High Strength ◽  
Polymerization Process ◽  
Component Selection ◽  
Materials Used ◽  
Pigmented Coatings

In the dissertation compositions of urethane diacrylates and monoacrylates have been studied, which when curing under the conditions of UV-activated copolymerization process meeting the requirements of cosmetic varnishes, form cross-linked structure coatings with high strength-deformation, surface hardness, surface light reflectance, adhesion and other parameters. The review of the literature summarizes information on the types of natural nail coatings and the basic components entering them. Restrictions on the choice of basic components entering the system are described. The effect of conditions and components on the natural nail is described. The materials used in the research are described in the methodological part of the work. The process of obtaining compositions is described. The research methods used are described: characterization of rheological properties of non-polymerized compositions, differential thermal analysis of polymerization process, determination of polymerization depth, determination of crosslinked part of polymerized systems, determination of yield tensile strength-deformation, coating surface hardness, surface gloss and surface wear, assessment of adhesion and its durability, in-vitro and in-vivo coating adhesion studies on natural nails, spectroscopic analysis of pigmented coatings and assessment of color constancy, comparison of coating compositions in terms of their functionality and effects on human health. In the experimental part of the work, methodologies for component selection, composite system formation and obtaining appropriate coatings have been developed. A methodology has been developed for the evaluation of the set of structures and properties of the obtained coatings. The influence of the chemical nature and content ratios of urethane diacrylates and monoacrylates suitable for the formation of separate cosmetic coatings on the indicators of cross-linked structures formed in the process of UV-activated copolymerization and the corresponding indicators of coating properties has been studied. The influence of individual additives on the properties of cross-linked coatings, their adhesion to the surface and the durability of the coating at removal process has been evaluated.

New materials from degraded styrene-acrylonitrile and ethylene-propylene-diene copolymers

e-Polymers ◽  
2004 ◽  
Vol 4 (1) ◽  
Author(s):  
Jasminka Vugrinec ◽  
Ljerka Kratofil ◽  
Zlata Hrnjak-Murgić ◽  
Jasenka Jelenčić
Keyword(s):  
Ir Spectroscopy ◽  
Polymer Blends ◽  
Graft Copolymer ◽  
Chloroform Solution ◽  
Polymerization Process ◽  
Time Interval ◽  
Grafting Reaction ◽  
Styrene Acrylonitrile

Abstract Polymer blends of styrene-acrylonitrile (SAN) and ethylene-propylenediene copolymer (EPDM) were prepared by casting films from chloroform solution. Their compositions were 95/5, 90/10 and 80/20, respectively. To simulate ageing, SAN/EPDM blends were degraded at 140°C for several different time intervals and the degree of degradation was followed by IR spectroscopy and by determination of molar masses. To recover thermally degraded SAN/EPDM blends, in situ polymerization by addition of styrene monomer was applied. Characterization of SAN and EPDM, graft copolymer and gel was carried out in order to reveal the polymerization process. Extractions of the polymers were made using solvents in a Soxhlet equipment: SAN in a mixture of acetone/ methanol, EPDM in hexane, graft copolymer in tetrahydrofuran, while the remaining part was considered as gel. Identification of extracted polymers has been conducted by IR spectroscopy. The presence of graft copolymer in the polymerization mixture proved the grafting reaction of polymer radicals. The highest content of graft copolymer was obtained for SAN/EPDM polymer blends that were exposed to thermal treatment for the longest time interval of 90 h.

Determination of fluoride ions released from resin-based dental materials using ion-selective electrode and ion chromatograph

2004 ◽  
Vol 32 (2) ◽  
pp. 117-122 ◽  
Author(s):  
Toshiyuki Itota ◽  
Thomas E. Carrick ◽  
Sandra Rusby ◽  
Omar Taha Al-Naimi ◽  
Masahiro Yoshiyama ◽  
...  
Keyword(s):  
Dental Materials ◽  
Ion Selective Electrode ◽  
Selective Electrode ◽  
Fluoride Ions ◽  
Ion Chromatograph

Determination of dose rates from natural radionuclides in dental materials

2006 ◽  
Vol 91 (1-2) ◽  
pp. 15-26 ◽  
Author(s):  
I. Veronese ◽  
G. Guzzi ◽  
A. Giussani ◽  
M.C. Cantone ◽  
D. Ripamonti
Keyword(s):  
Natural Radionuclides ◽  
Dental Materials ◽  
Dose Rates

A Combined Physical–Chemical Polymerization Process for Fabrication of Nanoparticle–Hydrogel Sensing Materials

2012 ◽  
Vol 45 (20) ◽  
pp. 8382-8386 ◽  
Author(s):  
Qingzhou Cui ◽  
Wei Wang ◽  
Baohua Gu ◽  
Liyuan Liang
Keyword(s):  
Polymerization Process ◽  
Chemical Polymerization ◽  
Physical Chemical

scholarly journals Synthesis of polar copolymers by the process of emulsion via free radicals (FRP)

2019 ◽  
pp. 1-5
Author(s):  
Luis Mario Magaña-Maldonado ◽  
David Contreras-López
Keyword(s):  
Free Radicals ◽  
Batch Reactor ◽  
Operating Conditions ◽  
Polymerization Process ◽  
Optimal Operating ◽  
Molecular Weights ◽  
Polymer Industry ◽  
The Impact ◽  
Vinyl Propionate

At present, the polymer industry has gained increasing importance due to the versatility of its properties, as well as the impact they have on the environment. The present investigation provides the determination of optimal operating conditions for the polymerization of styrene and vinyl propionate in a Batch reactor, as well as the copolymerization of styrene with propionate monomers by the process of emulsion via free radicals, allowing to observe the variations with respect to Reaction yields and molecular weights. Another important factor is the activation of the initiator so that the polymerization process begins within each of the micelles. Likewise, it was found that, in the copolymerizations, there are considerable variations with respect to reaction yields and molecular weights as the concentrations are modified. In addition, it was found that there are higher yields in styrene polymerizations per solution than emulsion.

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