Properties of Polymer-Composite Used as Fills of Asian Lacquerware: Issues on Restoration Processes of Lacquered Objects from Cultural Heritage

One of the common problems encountered in lacquerware issued from cultural heritage is the appearance of lifting areas and some losses of material. Composite systems made of commercial polymer and different fills were tested as filling agents for the cracking, splitting, and losses compensation of Asian lacquer. For that purpose, the stability of traditional and modern commercially available materials usually used in the restoration practice of historical lacquerware was assessed. Their thermomechanical and chemical properties and surface state were evaluated by a set of techniques (TGA, DMA, mechanical test, contact angle value, and microtopography). There is a drastic change of the behavior of the interface between fill and Asian lacquer, dependent on the nature of the composite fillers. So the evaluation of materials and processes for the restoration of Asian lacquer were emphasized. The commercial Paraloid B72 used with glass microspheres as additives appeared to be the most stable of all of the investigated fillers

Effets du nettoyage et du conditionnement sur la dégradation des PVC plastifiés

Le polychlorure de vinyle plastifié est un polymère synthétique, largement utilisé depuis le milieu du xxe siècle et jusqu’à nos jours, pour la production d’œuvres d’art et d’objets. Son état de conservation est souvent médiocre en raison de la migration des plastifiants. L’étude de l’impact du nettoyage et du mode de conditionnement de PVC vieillis naturellement en environnement muséal sur leur évolution permet d’envisager des conditions de conservation préventives et curatives optimales afin d’en limiter les dégradations.Plasticized polyvinyl chloride is a synthetic polymer, widely used from the mid-20th century until today in the production of artworks and artefacts. Its condition is often mediocre owing to the migration of plasticizers. The study of the impact of cleaning and conditioning on the evolution of naturally ageing PVCs in a museum environment has enabled us to envisage optimum conditions for preventive conservation so as to mitigate the degradation process

Photochromic and Electrochromic N-Salicyldene (anil) Functionalized Carbazole and bis EDOT-Carbazole.

Abstract not Available.</jats:p

Development of organic glass using Interpenetrating Polymer Networks with enhanced resistance towards scratches and solvents

International audienc

Development of organic glass using Interpenetrating PolymerNetworks with enhanced resistance towards scratches andsolvents

International audienceAcrylate polymers are one of common organic glass family. However their sensitivity toabrasion is an important drawback. Various alternatives were considered but they are oftenexpensive. In this work, we show that the polymethylmethacrylate (PMMA) glassresistance can be improved by performing materials based on Interpenetrating PolymerNetwork (IPN) at low cost. A series of transparent IPNs based on an aliphatic polycarbonateand PMMA was synthesized through in situ polymerization process. The formation of twonetworks in the IPNs was studied by FTIR spectroscopy. Effects of PMMA cross-linking andpartner proportions in the IPNs were investigated by dynamic mechanical thermalanalysis. Optical properties, solvent and scratch resistances have been also studied

DEVELOPMENT OF A NEW POLYMER GLASS WITH ENHANCED RESISTANCE TOWARDS SCRATCHES AND SOLVENT FOR CULTURAL HERITAGE

International audienceIn the particular context of cultural heritage, protective glazing has been the subject of only few studies [1-2]. In addition to the monitoring of temperature, humidity and light in museums, the conditions of conservation for the preservation of cultural heritage, needs the development of a low cost glass with specific properties.Poly(methyl methacrylate) (PMMA) is one of the most widely used compounds in the manufacture of organic glasses. Indeed it has a refractive index (n = 1.491) close to that of glass (n = 1.522), it has a better light transmission and is much lighter and less brittle than glass. Therefore it has been widely applied in conservation for the glassing of artifacts and especially during travelling exhibitions. PMMA is also still used by many artists to produce artworks such as Diasec© (a popular face mounting techniques for photographs), 3D objects and design furnitures. Unfortunately PMMA is very sensitive to abrasion and after a few years this might alter the visual appearance of the artifact. This work shows the possibility to enhance anti-scratch and solvents resistance of PMMA based glass by combining it with polycarbonate (PCR39®) inside Interpenetrating Polymer Network (IPN) architecture. Our specifications require a transparent final material and a preparation without solvent in order to address specific issue of the cultural heritage preservation community. These IPNs are synthesized according to an in situ process. According to the chosen free-radical initiators, the PMMA network is formed in the first place followed by the synthesis of PCR39® network. Rigid transparent (transmission higher than 95%) materials are obtained. Thermomechanical analyses indicate a correct interpenetration of both networks. The scratch and solvents tests show that the addition of PCR39® to PMMA in the IPN improves each of these properties and furthermore the glass ability to filter a part of UV radiations

Synthesis, Electrochemical and Spectroscopic Investigations of New N-BEDOT Derivatives Containing Anil Substituted Carbazole Subunits

Abstract not Available.</jats:p