scholarly journals Plastics in Heritage Collections: Poly(vinyl chloride) Degradation and Characterization

2020 ◽  
Vol 67 (4) ◽  
pp. 993-1013
Author(s):  
Tjaša Rijavec
Keyword(s):  
Vinyl Chloride ◽  
Degradation Products ◽  
Systematic Research ◽  
Preventive Conservation ◽  
Dsc Studies ◽  
Poly Vinyl Chloride ◽  
Multi Stage ◽  
Plastic Materials ◽  
Conjugated Polyenes ◽  
Heritage Collections

Museums and galleries house increasingly large collections of objects and contemporary art made of plastic materials, many of which undergo rapid material change. The main degradation processes of poly(vinyl chloride) (PVC) are elimination of HCl and plasticizer migration or leaching. This results in visible discolouration, stickiness and cracking. Degradation is known to be a multi-stage process that includes HCl elimination, formation of conjugated polyenes and cross-linking. Elimination of HCl begins due to structural irregularities (allylic and tertiary chlorides) and results in the formation of polyenes. When at least 7 conjugated double bonds are present, discolouration of PVC becomes visible. Non-invasive techniques, such as IR and Raman spectroscopy are used for polymer identification and plasticizer quantification. Plasticizer degradation and particularly the late stages of PVC degradation can be investigated using SEC, GC-MS, TGA and DSC. Studies in heritage collections have revealed that, apart from HCl, PVC objects emit 2-ethylhexanol and other volatile degradation products, however, there is currently no indication that HCl is emitted at usual indoor conditions. There seems to be a general lack of systematic research into PVC degradation at the conditions of storage and display, which could result in the development of dose-response functions and in the development of preventive conservation guidelines for the management of PVC collections.

scholarly journals Novel Tailor made Multiblock Polyesters/Polycarbonates Biomaterials via Organometallic Polymerization Synthesis

2021 ◽  
pp. 460-462
Author(s):  
Bolley A
Keyword(s):  
Vinyl Chloride ◽  
Mass Production ◽  
Electronic Devices ◽  
Poly Vinyl Chloride ◽  
Plastic Materials ◽  
Wide Range

Since 1940, mass production of polyolefin plastics produced annually has increased rapidly [1]. The most common plastics, which account for approximately 80% of the European plastic demand, are: Polyethylene (PE), Polypropylene (PP), Poly (Vinyl Chloride) (PVC) and Polystyrene (PS) (Figure 1) [2]. Therefore, plastic materials have experienced a substantial expansion, and are the most used materials nowadays. These materials have a wide range of application from packaging to electronic devices [3].

DSC studies of poly(vinyl chloride)/poly(ε-caprolactone)/poly(ε-caprolactone)-b-poly(dimethylsiloxane) blends

2009 ◽  
Vol 63 (4) ◽  
pp. 517-529 ◽  
Author(s):  
Claudia Gordin ◽  
Christelle Delaite ◽  
Sophie Bistac ◽  
Daniela Rusu ◽  
Mihai Rusu
Keyword(s):  
Vinyl Chloride ◽  
Dsc Studies ◽  
Poly Vinyl Chloride

scholarly journals Synthesis of New Thiophene Derivatives and Their Use as Photostabilizers for Rigid Poly(vinyl chloride)

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Asim A. Balakit ◽  
Ahmed Ahmed ◽  
Gamal A. El-Hiti ◽  
Keith Smith ◽  
Emad Yousif
Keyword(s):  
Excited State ◽  
Vinyl Chloride ◽  
Degradation Products ◽  
Chain Scission ◽  
Direct Absorption ◽  
Absorption Bands ◽  
Poly Vinyl Chloride ◽  
Rigid Poly ◽  
Thiophene Derivatives ◽  
Infrared Absorption Bands

Five new thiophenes, namely,N-[(3-bromo-2-methylthiophen-5-yl)methylene]-4-methoxyaniline (4a),N-[(3-bromo-2-methylthiophen-5-yl)methylene]-3,4-dimethoxyaniline (4b),N-[(3-bromo-2-methylthiophen-5-yl)methylene]-3,4-dimethylaniline (4c), 3-[(3-bromo-2-methylthiophen-5-yl)methyleneamino]-2-methylquinazolin-4(3H)-one (4d), and 3-[(3-bromo-2-methylthiophen-5-yl)methyleneamino]-2-isopropylquinazolin-4(3H)-one (4e), have been synthesized. All of these materials brought about a reduction in the level of photodegradation of poly(vinyl chloride) (PVC) films containing the synthesized thiophenes (0.5%; by weight). The results obtained showed that the extent of photostabilization of PVC in the presence of an additive was in the order4e > 4d > 4b > 4a > 4c. For the most favorable additive (4e), the rate of appearance of infrared absorption bands of degradation products was reduced by around two-thirds, while the quantum yield of chain scission was calculated to be reduced by a factor of more than one thousand. It is suggested that the additives may help stabilize PVC by direct absorption of UV radiation and dissipation of the energy as heat or that electrostatic attraction between the additives and PVC may assist transfer of energy from excited state PVC to the additive, from where it can be dissipated.

scholarly journals Effect of Organoclay on the Morphology, and Thermal Properties of Polystyrene/Poly (vinyl chloride) Nanocomposites

2015 ◽  
Vol 1 (2) ◽  
Author(s):  
Jumaa Aseeri - Waffa Mekhamer -  Naser Alandis
Keyword(s):  
Vinyl Chloride ◽  
Cetylpyridinium Chloride ◽  
Clay Sample ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Dsc Studies ◽  
Poly Vinyl Chloride ◽  
Transmission Electron ◽  
Before And After ◽  
Na Ions

Polystyrene and poly (vinyl chloride) (PS/PVC) were prepared via solvent casting method with different weight ratios of PS/PVC:  (100/0, 90/10, 80/20, 10/90 and 0/100) to investigate their miscibility. We have studied the morphology of blend PS90/PVC10 (Pd1) with different content (1, 3, 10 %) of organoclay (MM). Cetylpyridinium chloride (CPC) is used to modify the clay sample after saturating its surface with Na+ ions. Fourier transform infrared (FTIR), X-ray diffraction (XRD), and transmission electron microscopy (TEM) were used to characterize the clay sample before and after modification by CPC. The blend miscibility has been confirmed by FTIR, XRD, differential scanning calorimetry (DSC) studies.  The prepared nanocomposites were characterized using FTIR, DSC, TEM and scanning electron microscope (SEM). We observed that MM have a significant effect on improvement the miscibility of PS/PVC blends. The thermal stability of the nanocomposites was measured using thermogravimetric analysis (TGA).

scholarly journals Plasticiser loss in heritage collections: its prevalence, cause, effect, and methods for analysis

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Rose King ◽  
Josep Grau-Bové ◽  
Katherine Curran
Keyword(s):  
Indoor Air ◽  
Science Research ◽  
Conservation Practices ◽  
Preventive Conservation ◽  
Migration Rates ◽  
Poly Vinyl Chloride ◽  
Surrounding Environment ◽  
Heritage Science ◽  
Non Destructive ◽  
Heritage Collections

AbstractPlasticiser loss is a topic frequently mentioned in discussions on the degradation of plastic artefacts in museum collections, particularly for plasticised poly (vinyl chloride) and cellulose acetate. Plasticisers may migrate to the plastic’s surface and remain as a deposit, or volatilise into the surrounding environment, both presenting an aesthetic issue and impacting the future stability of the plastic. This paper draws on the work of conservation science, materials degradation, and indoor air quality/emissions studies, to review our current understanding of plasticiser loss. The influence of the material’s intrinsic properties, and environmental factors on migration rates are discussed and related to preventive conservation practices. The methods by which plasticiser migration is studied, including characterisation, are also reviewed, with a particular focus on minimally invasive and non-destructive methods suitable for heritage science research.

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