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TOSGN10002 / TOSGB10001

In document LÍNEA BLANCA RI 600 RI 580 (página 36-43)

PVAL is unique among synthetic polymers. Although made from oil-based feedstock, this polymer has an inherent ability to be biodegraded. With properties once regarded as a scientific curiosity and a niche market which utilises its inherent water solubility and with biocompatibility and biodegradable credentials, this material is likely to expand further into markets in which biopolymers and biodegradable materials (namely short life consumer products and medical applications) are likely to dominate in future.

With biodegradable plastics materials likely to become more valuable as land fill operations seek to divert such waste, it is unclear how this may affect the prospects for biodegradable plastics in the marketplace unless prices become more commercially comparable with traditional commodity plastics. Blending of materials may provide one method to limit the cost penalties but the wide scale implications for waste disposal and expanding recycling

capacity if such materials are used is also uncertain. However with increasing pressure for sustainability to be bought to bare from the EU, significant shifts both in the marketplace and disposal infrastructure will have to occur to meet the waste targets.

References

a.1 BS EN ISO 15023-1, Plastics - Poly(vinyl alcohol) PVAL Materials - Part 1: Designation System and Basis for Specification, 2006. a.2 DIN 53015, Viscometry - Measurement of

viscosity by means of the rolling ball viscometer by Hoppler, 2001.

a.3 Japan Chemical Week, 2006, 47, No.2385, 8. a.4 N. Preston, Flexible, 2006, 4, 5, 40.

a.5 M. Kokabi, M. Sirousazar and Z.M. Hassan, European Polymer Journal, 2007, 43, 3, 773. a.6 F.F. Nord, Naturwiss 1936, 24, 763.

a.7 E. Chiellini, A. Corti, S. D’Antone and R. Solaro, Progress in Polymer Science, 2003,

28, 963.

a.8 The European Directive on WEEE (Directive 2002/96/EC)

a.9 Plastics Technology, 2004, 50, 10, 32. a.10 Plastics Technology, 2007, 53, 2, 60.

a.11 ASTM D882, Test Method for Tensile Properties of Thin Plastic Sheeting, 2002. a.12 ASTM D1004, Test Methods for Tear

Resistance (Graves Tear) of Plastic Film and Sheeting, 2008.

a.13 ASTM D5226, Practice for Dissolving Polymer Materials, 2003.

a.14 E.R. Kenaway P. Cinelli A. Corti S. Miertus and E. Chiellini, Macromolecular Symposia, 1999; 144, 351.

a.15 K. Pal, A.K. Banthia and D.K. Majumdar, AAPS PharmSciTech, 2007, 8, 1, Article 21. a.16 A. Srivastava, Popular Plastics and Packaging,

2004, 49, 1, 87.

a.17 EN13432, Packaging - Requirements for Packaging Recoverable Through Composting

and Biodegradation - Test Scheme and Evaluation Criteria for the Final Acceptance of Packaging, 2005.

a.17 G. Scott, Polymer Degradation and Stability, 2000, 68, 1.

a.18 End-of-Life Vehicle (ELV) Directive [Directive 2000/53/EC]

a.18 M. Heyde, Polymer Degradation and Stability, 1998, 59, 1-3, 3.

a.19 R.Chandra and R. Rustgi, Progress in Polymer Science, 1998, 23, 1273.

a.20 P. Nayak, Review of Macromolecular Chemistry and Physics, 1999, 39, 3, 481.

Abbreviations and Acronyms

ASTM American Society of Testing and Materials CRT Cathode ray tube(s)

EAP Environmental Action Programme(s) ELV End-of-life vehicle

EU European Union EVOH Ethylene vinyl alcohol HDPE High-density polyethylene IPP Integrated product policy LCA Life cycle analysis(es) LCD Liquid crystal display(s) LDPE Low-density polyethylene LLDPE Linear low-density polyethylene OPP Orientated polypropylene PA Polyamide

PBS Polybutylene succinate PCL Poly-E-caprolactone PDP Plasma display panel(s) PE Polyethylene

PET Polyethylene terephthalate PHA Polyhydroxyalkonoates PHB Polyhydroxybutyrate PHBV Poly(hydroxybutyrate-co-

hydroxylvaleratevalerate) PLA Poly(lactic acid)

PP Polypropylene PVAc Polyvinyl acetate PVAL Poly(vinyl alcohol) PVB Poly(vinyl butyral) PVC Polyvinyl chloride PVDC Poly(vinylidene chloride) TPS Thermoplastic starch UV Ultraviolet

Abstracts from the Polymer Library Database

Item 1

Advanced Functional Materials

18, No.19, 2008, p.2946

SURFACTANT-FREE SELF-ASSEMBLED PVA-IRON OXIDE/SILICA CORE-SHELL NANOCARRIERS FOR HIGHLY SENSITIVE MAGNETICALLY CONTROLLED DRUG RELEASE AND ULTRAHIGH CANCER CELL UPTAKE EFFICIENCY

Hu S-H; Liu D-M; Tung W-L; Liao C-F; Chen S-Y The synthesis of surfactant-free self-assembled poly(vinyl alcohol)(PVA)-iron oxide/silica core-shell nanocarriers by encapsulation of monodispersed magnetic iron oxide particles derived by high temperature decomposition of ferric acetylacetonate and a model hydrophobic drug such as ibuprofen using PVA as binder followed by coating with a thin shell of silica by hydrolysis and condensation of tetraethyl orthosilicate is described. The products were characterised by FE-SEM TEM SQUID magnetometry and XRD and their controlled drug release properties under an external magnetic field were investigated by UV-visible spectroscopy. 28 refs.

Taiwan National Chiao Tung University

TAIWAN

Accession no. 1030215 Item 2

Advanced Functional Materials

18, No.19, 2008, p.2855

A NOVEL CROSS-LINKED POLY(VINYL ALCOHOL) (PVA) FOR VASCULAR GRAFTS Chaouat M; Le Visage C; Baille W E; Escoubet B; Chaubet F; Mateescu M A; Letourneur D

The fabrication of crosslinked poly(vinyl alcohol)(PVA) films by aqueous solution casting in the presence of sodium trimetaphosphate as crosslinking agent and their characterisation by DMA and by biocompatibility via cell culture studies is described. The fabrication of small diameter tubes based on the crosslinked PVA films via a gluing procedure with cyanoacrylate adhesive was investigated and their evaluation as potential vascular grafts by in-vitro and in-vivo testing is discussed in terms of mechanical properties such as compliance elasticity and resistance to mechanical stress compatible with circulatory blood flow. 31 refs.

INSERM; Montreal University; Paris VII Universite; Paris XIII Universite

CANADA; EUROPEAN COMMUNITY; EUROPEAN UNION; FRANCE; WESTERN EUROPE

Accession no. 1030209

Item 3

Polymer

49, No.21, 2008, p.4740

TRANSITION OF HYDRATION STATES OF POLY(VINYL ALCOHOL) IN AQUEOUS SOLUTION

Wenbo Li; Yun Zheng; Rongshi Cheng

A straightforward method for determination of the hydration number of polymer in aqueous solution based on ice-melting technique of DSC is proposed. The simple yet precise method has been applied to determine the hydration number of poly(vinyl alcohol) (PVA) in aqueous solution covering a wide range of concentrations from 0.005 to 0.3 g(solute)/g(solution) for three samples with different molar masses. The hydration number of PVA maintains a constant lower value of 2.5 when the concentration exceeds 0.2 g(solute)/g(solution). It increases to a value of 7 when the concentration decreases to the overlap concentration C*of the polymer where C*was estimated as the reciprocal of its intrinsic viscosity. For solutions of C<C* the hydration number keeps constant again at the value of 7. This behaviour evidently demonstrates that PVA has two hydration states one occurs at the dilute regime and the other occurs at concentrated regime. The concentration dependent transition from one state to another is treated mathematically by a quantitative formula which involves two parameters: one denotes the transition concentration and the other denotes the width of the transition region. The transition concentration decreases linearly with increasing molar mass resembling the behaviour of molar mass dependence of overlap concentration. The structural features for the two states of hydrated PVA are briefly discussed. 19 refs. Copyright (c) 2008 Elsevier Ltd. Nanjing University; South China University of Technology CHINA Accession no. 1029966 Item 4 Polymer Preprints 2008, 49, No.2, p.343 SYNTHESIS OF POLY(VINYLACETYLENE) BLOCK COPOLYMERS AS PRECURSORS FOR NANOCARBON MATERIALS

Aimi J; McCullough L A; McGann J; Kowalewski T; Matyjaszewski K

Poly(vinylacetylene) (PVA)-containing block copolymers were synthesised via activators regenerated by electron transfer (ARGET) atom transfer radical polymerisation (ATRP). The active acetylenic hydrogen atom in vinylacetylene was substituted by the trimethylsilyl group in order to prevent 14-polymerisation. In the homopolymerisation of trimethylsilyl-protected

vinylacetylene (VA-TMS) it was found that a lower temperature prevented side reactions and gave a well- controlled polymer with low polydispersity. The desilylated homopolymer of PVA-TMS was easily crosslinked to give an insoluble polymer. A block copolymer of PMMA-b- PVA was also synthesised by ATRP. This block copolymer seemed miscible thus block copolymerisation overcame the insolubility of the deprotected homopolymer. Nanocarbon materials could be prepared by pyrolysis of PVA-containing block copolymers. 7 refs.

Carnegie-Mellon University; Washington D.C

USA

Accession no. 1029567 Item 5

Journal of Applied Polymer Science

110, No.3, 2008, p.1784

KINETIC STUDY OF THE FREE-RADICAL POLYMERIZATION OF VINYL ACETATE IN THE PRESENCE OF DEUTERATED

CHLOROFORM BY 1H-NMR SPECTROSCOPY

Semsarzadeh M A; Abdollahi M

Real time nuclear magnetic resonance spectroscopy was used to study the kinetics of the free radical polymerisation of vinyl acetate using deuterated chloroform as chain transfer agent and azobisisobutyronitrile as initiator. Effects of the concentrations of initiator and solvent on reaction kinetics were evaluated and kinetic parameters such as rate and transfer constants and initiator efficiency were calculated. It was shown that both temperature and solvent concentration affect initiator dissociation rate constant but initiator concentration does not. The solvent concentration was found to have an effect on both initiator efficiency and termination rate constant. 60 refs. Tarbiat Modarres University

IRAN

Accession no. 1029333 Item 6

Journal of Applied Polymer Science

110, No.3, 2008, p.1632

INFLUENCE OF HIGH PRESSURE GASES ON POLYMER-SOLVENT THERMODYNAMIC AND TRANSPORT BEHAVIOR

Jones A T; Danner R P; Duda J L

The use of soluble gases as co-solvent in the devolatilisation process for removal of residual solvents and monomers in the polymerisation process was investigated using either carbon dioxide or ethylene with polystyrene or polyvinyl acetate. The introduction of the gas was found to reduce polymer solubility and increase solvent diffusivity and ethylene was found to have the most effect. Gas chromatography was used in the analysis of solvent removal and the work demonstrated the potential for increasing production rates in polymerisation process by exchanging the

normal non-interacting gases such as nitrogen or air by a soluble gas. 18 refs.

Pennsylvania State University

USA

Accession no. 1029314 Item 7

Polymer Reprints

49, No.2, 2008

PHOTOINDUCED LIVING RADICAL

POLYMERIZATION WITH HIGHLY ACTIVE MANGANESE COMPLEX

Koumura K; Satoh K; Kamigaito M

Efficient controlled radical polymerisation of vinyl acetate (VAc) methyl acrylate (MA) or styrene (St) occurred in the presence of a system comprising ethyl iodoacetate or ethyl 2-iodo-2-methylpropanoate and dimanganese dodecacarbonyl under visible light irradiation. The polymerisation of VAc was rapid and efficient and gave a polymer with a controlled molecular weight even at a low concentration of Mn2(CO)10. The polymerisations of MA and St also gave polymers with controlled molecular weights. 4 refs.

Nagoya University; Washington D.C.

JAPAN; USA

Accession no. 1029046 Item 8

Pharmaceutical Technology Europe

20, No.10, 2008, p.32

PVA COPOLYMER: THE NEW COATING AGENT FUJII T; NOAMI M; TOMITA K; FURUYA Y The commercial development of a copolymer of vinyl alcohol with acrylic acid and methyl methacrylate as a sprayable film coating agent for tablets and microparticles is described. The copolymer was characterised by solubility and viscosity in water DSC oxygen permeability the strength of film adhesion to the tablet core drug dissolution properties and impact strength and the results are discussed in comparison with those for hydroxypropyl methylcellulose as control in terms of pharmaceutical applications. 10 refs.

Shionogi and Co.Ltd.

JAPAN

Accession no. 1028318 Item 9

Journal of Materials Science

43, No.17, 2008, p.5898

TWO-STEP SYNTHESIS OF POLYACRYLAMIDE/ POLY(VINYL ALCOHOL)/POLYACRYLAMIDE/ GRAPHITE INTERPENETRATING NETWORK HYDROGEL AND ITS SWELLING CONDUCTING AND MECHANICAL PROPERTIES

The two-step synthesis of poly(acrylamide)/poly(vinyl alcohol)(PVA)/polyacrylamide/graphite interpenetrating network hydrogels by initial radical polymerisation of acrylamide in the presence of PVA and graphite micropowder with potassium persulphate as initiator followed by a subsequent radical polymerisation of acrylamide and NN'-methylene bisacrylamide as crosslinking agent is described. The hydrogels were characterised by FTIR TGA electrical conductivity and tensile properties and the effects of PVA graphite and crosslinking agent contents on swelling properties of the hydrogels are discussed. 39 refs.

Huaqiao University

CHINA

Accession no. 1028239 Item 10

FujianKey Laboratory of Polymer Materials Composites Part A

39, No.10, 2008, p.1638

CELLULOSE NANOFIBER REINFORCED POLY(VINYL ALCOHOL) COMPOSITE FILM WITH HIGH VISIBLE LIGHT TRANSMITTANCE Chunyi Tang; Haiqing Liu

In this paper we presented the fabrication and characterisation of poly(vinyl alcohol) (PVA) composite film reinforced with high volume of electrospun cellulose nanofibrous mat (CNM). Its visible light transmittance and mechanical properties were examined in relation to fibre content in the composite. Optimal CNM content in the composite was found to be 40wt% in terms of its overall properties. This composite film exhibited visible light transmittance of 75% and its mechanical strength and Young's modulus were increased by 50% and 600% respectively as compared to neat PVA film. 22 refs. Fujian Normal University

CHINA

Accession no. 1028058 Item 11

Materials Letters

62, No.28, 2008, p.4380

MECHANICAL STRENGTH IMPROVEMENT OF POLYPROPYLENE THREADS MODIFIED BY PVA/CNT COMPOSITE COATINGS

Bo Zhao; Jing Wang; Zijiong Li; Ping Liu; Da Chen; Yafei Zhang

Poly (vinyl alcohol)/carbon nanotube (PVA/CNT) composite was coated on the surface of polypropylene thread for toughness enhancement. Multiwall carbon nanotubes (MWNTs) were treated in acid and alkali to get water-soluble nanotubes and then embedded into poly (vinyl alcohol) (PVA) matrix resulting in polymer-carbon composite with homogeneous nanotube dispersion. The stress-strain measurements show that the tensile strength and toughness of the PVA/CNT coated thread increased by

117% and 560% respectively. These results are supportive of good interfacial bonding between the carbon nanotubes (CNTs) and polymer matrix. 10 refs.

Shanghai Jiao Tong University

CHINA

Accession no. 1028026 Item 12

Adhesive & Sealant Council Inc.

2008, 70 papers WAC & EXPO 2008

Proceedings of the 2008 World Adhesive Conference and Expo held Miami Fl. 20-23 April 2008 Seventy papers were presented at the 2008 World Adhesive Conference. Topics addressed include: advancing end-use technologies; international regulations update; reactive adhesives; REACH: Understanding and compliance; advances in formulation; future trends in pressure-sensitive adhesives; and renewable resources.

USA; WORLD

Accession no. 1027981 Item 13

Journal of Polymer Science: Polymer Chemistry Edition

46, No.19, 2008, p.6407

PARTICLE NUCLEATION IN HIGH SOLIDS BATCH MINIEMULSION POLYMERIZATION STABILIZED WITH A POLYMERIC

SURFACTANT Bohorquez S J; Asua J M

The nucleation of polymer particles in the miniemulsion polymerisation of vinyl acetate and vinyl ester stabilised with PVOH was studied. The effect of costabiliser type PVOH concentration and type and concentration of initiator on the extent of droplet nucleation were studied. Droplet nucleation was maximised by improving miniemulsion stability and using efficient initiators. 35 refs.

Basque Country University

SPAIN

Accession no. 1027661 Item 14

Estadual Polymer

49, No.19, 2008, p.4066

MULTIPLE HYDROPHILIC POLYMER ULTRA- THIN LAYERS COVALENTLY ANCHORED TO POLYETHYLENE FILMS

Silva R; Muniz E C; Rubira A F

A novel procedure has been developed to covalently graft multiple hydrophilic polymer ultra-thin layers to functionalised polyethylene surface. Polyethylene films have been functionalised by two methods chromic acid oxidation and maleic anhydride grafting to produce surfaces containing reactive groups carboxylic acid and

anhydride respectively. The reactive groups formed in the functionalisation were used to anchor a poly(vinyl alcohol) (PVA) ultra-thin layer by thermal esterification. After anchoring PVA a second ultra-thin layer constituted of poly(acrylic acid) (PAA) was also anchored. The second layer was anchored by thermal esterification between PVA hydroxyl groups and PAA carboxylic acid groups. The procedure presented in this work allows the formation of an ultra-thin layer. The macromolecule anchoring reactions occur only at the interfaces consequently only the macromolecules in contact with the interface are anchored. The formation of the ultra-thin layer and the surface characteristics have been analyzed through XPS ATR-FTIR SEM and AFM data. 41 refs.

Maringa Universidade Estadual

BRAZIL

Accession no. 1027532 Item 15

Journal of Applied Polymer Science

110, No.2, 2008, p.1136

PREPARATION OF A MULTISTRUCTURAL FILM WITH CM-CHITOSAN AND PVA AND IN VITRO ORNIDAZOLE RELEASE FROM THE CARRIER

Ling Chong Wang; Xi Guang Chen; Cheng Sheng Liu; Li De Li; Qiu Xia Ji; Le Jun Yu

Using ornidazole as a model drug carboxymethyl chitosan drug-containing microspheres (CCMS) were prepared by a method involving emulsification solidification and drug loading. A multistructure drug system was then synthesised by incorporating these microspheres into polyvinyl alcohol (PVAl). The multi-stage system allowed control of drug loading encapsulation efficiency and drug release. Drug release from the combined system of CCMS and PVAl was slightly faster than from CCMS alone and followed a profile of a burst release followed by gradual release of the remaining drug. Microspheres were characterised using optical microscopy a particle size analyser and swelling measurements. Drug loading was determined by ultraviolet visible spectroscopy and drug release studies were carried out in-vitro. 22 refs.

Qingdao Ocean University; Qingdao University

CHINA

Accession no. 1027503 Item 16

Journal of Applied Polymer Science

110, No.2, 2008, p.695

POTENTIAL APPLICATIONS OF POLY(VINYL ALCOHOL)-CONGO RED AQUEOUS

SOLUTIONS AND HYDROGELS AS LIQUIDS FOR HYDRAULIC FRACTURING

Vega I; Fernandez E; Mijangos C; D'Accorso N; Lopez D A comparison was made of the viscoelastic properties of hydrogels and solutions based on congo red crosslinked

polyvinyl alcohol (PVA) or guar gum/borax complexes. Effects of concentrations of PVA and congo red and of the degree of hydrolysis on viscoelastic properties were also evaluated. The application of the PVA/Congo red system as a hydraulic fracturing liquid rather than the more commonly used guar gum/borax system was discussed and some advantages were reported. 20 refs.

Buenos Aires University

ARGENTINA; EUROPEAN COMMUNITY; EUROPEAN UNION; SPAIN; WESTERN EUROPE CSIC;

Accession no. 1027450 Item 17

Journal of Sol-Gel Science and Technology

47, No.3, 2008, p.243

POLYMER/SILICATE COMPOSITES: NEW MATERIALS FOR SUBSURFACE PERMEABLE REACTIVE BARRIERS

Harrup M K; Jones M G; Polson L; White B

The fabrication of composite membranes of polyacrylonitrile poly(ethylene oxide) poly(ethylene glycol) poly(vinyl acetate) and poly(vinyl alcohol) with silica and ammonium molybdophosphate as sequestrating agent and their characterisation by DMA TGA ESEM and caesium sequestration studies is described. The applications of the membranes as materials for sub-surface permeable reactive barriers are discussed in terms of the requirements of water permeability mechanical strength selective metal sequestration and ease of use. 26 refs.

Idaho National Laboratory

USA

Accession no. 1027385 Item 18

Harbin Northeast Forestry University Polymer Composites

29, No.9, 2008, p.998

PREPARATION AND CHARACTERIZATION OF CARBOXYMETHYL POLYVINYL ALCOHOL- GRAPHITE NANOSHEET COMPOSITES Yu C; Li B

Carboxymethyl polyvinyl alcohol (CMPVA) was prepared by introducing carboxymethyl groups to polyvinyl alcohol (PVA) with chloroacetic acid. Graphite nanosheets (NanoG) were obtained by treating expandable graphite at a high temperature in a muffle furnace and then sonicating it in an aqueous ethyl alcohol solution. Nanocomposites of CMPVA with NanoG were prepared by dispersing NanoG in a CMPVA aqueous solution with the aid of sonication and then casted on plastic film to remove water. Carboxymethyl groups were proved to be linked to PVA by Fourier transform infrared (FTIR) spectra and the degree of carboxymethyl substitution on the PVA was 2.77% determined by conductometric titration. Experimental results show that carboxylate anions in introduced carboxymethyl groups facilitate the dispersal

of NanoG with positive charges in the CMPVA solution. The CMPVA matrix was detected by X-ray diffraction (XRD) and FTIR spectra to be less crystal into which NanoG tend to disperse. Scanning electron microscopy was used to characterize the structure of the graphite and morphology of the composites to prove that NanoG was 40-70 nm thick. The percolation threshold of CMPVA/ NanoG composites at room temperature was as low as 0.80 wt%. 30 refs.

CHINA

Accession no. 1027294 Item 19

ANTEC 2008. Proceedings of the 66thAnnual Technical Conference held Milwaukee Wi

4th-8th May, 2008, p.2227

ADHESION OF PLASTICS WITH BONE: A COMPARATIVE STUDY USING

COMMERCIALLY AVAILABLE ADHESIVES AND BIODEGRADABLE POLYMER MELT ADHESIVES

Shrivastava A; Weinzwig J; McCarthy S

Biodegradable bone substitutes can be secured to bone surfaces using several techniques. One such technique is by using adhesives to glue the bone plates to the bone surface. This phenomenon has a potential of replacing the existing screws and the associated complex techniques and equipment. A time-based study comparing the adhesion of bone plates with bone using commercially available adhesives and biodegradable polymer melt adhesives was performed and the load bearing capacities were measured. This paper demonstrates and compares the effective use of adhesives and melt blends replacing the existing fixation techniques involved in craniomaxillofacial surgery. 18 refs.

Lowell Massachusetts University; Massachusetts Lahey Clinic Medical Center

USA

Accession no. 1026247 Item 20

ANTEC 2008. Proceedings of the 66thAnnual Technical Conference held Milwaukee Wi

4th-8th May, 2008, p.2148

INJECTION-MOULDED POLYMER SCAFFOLD FOAMS

Kramschuster A; Turng L S

In this research injection moulding was combined with a novel material combination supercritical fluid processing and particulate leaching techniques to produce highly porous structures that have the potential to act as scaffolds for tissue engineering applications. The foamed structures moulded with polylactide (PLA) and polyvinyl alcohol (PVOH) with salt as the particulate were processed without the aid of organic solvents which can be detrimental to tissue growth. Macropores approximately 200 microns in

diameter and porosities of approximately 75% are reported

In document LÍNEA BLANCA RI 600 RI 580 (página 36-43)

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