CEN TS 17158-2018 Composites made from cellulose based materials and thermoplastics (usually called wood polymer composites (WPC) or natural fibre composites (NFC)) - Determination.pdf

1、BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06Composites made from cellulose based materials and thermoplastics (usually called wood polymer composites (WPC) or natural fibre composites (NFC) - Determination of particle size of lignocellosic materialPD CEN/TS 17158

2、:2018National forewordThis Published Document is the UK implementation of CEN/TS 17158:2018.The UK participation in its preparation was entrusted to Technical Committee PRI/42, Fibre reinforced thermosetting plastics and prepregs.A list of organizations represented on this committee can be obtained

3、on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2018 Published by BSI Standards Limited 2018ISBN 978 0 539 00850 0ICS 83.140.99; 79.080; 83.080.01

4、Compliance with a British Standard cannot confer immunity from legal obligations.This Published Document was published under the authority of the Standards Policy and Strategy Committee on 31 May 2018.Amendments/corrigenda issued since publicationDate Text affectedPUBLISHED DOCUMENTPD CEN/TS 17158:2

5、018TECHNICAL SPECIFICATIONSPCIFICATION TECHNIQUETECHNISCHE SPEZIFIKATIONCEN/TS 17158April 2018ICS 79.080; 83.080.01; 83.140.99EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGCEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2018 CEN Re

6、f. No. CEN/TS 17158:2018: EAll rights of exploitation in any form and by any means reserved worldwide for CEN national MembersComposites made from cellulose based materials and thermoplastics (usually called wood polymer composites (WPC) or natural fibre composites (NFC) - Determination of particle

7、size of lignocellosic materialComposites base de matires cellulosiques et de thermoplastiques (communment appels composites bois-polymres (WPC) ou composites fibres dorigine naturelle (NFC) - Dtermination des dimensions de particles de matires ligocellulosiquesVerbundwerkstoffe aus cellulosehaltigen

8、 Materialien und Thermoplasten (blicherweise Holz-Polymer-Werkstoffe (WPC) oder Naturfaserverbundwerkstoffe (NFC) genannt) - Bestimmung der Partikelgre von lignocellulosehaltigem MaterialThis Technical Specification (CEN/TS) was approved by CEN on 10 December 2017 for provisional application.The per

9、iod of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit their comments, particularly on the question whether the CEN/TS can be converted into a European Standard.CEN members are required to announce the existence of this CEN/

10、TS in the same way as for an EN and to make the CEN/TS available promptly at national level in an appropriate form. It is permissible to keep conflicting national standards in force (in parallel to the CEN/TS) until the final decision about the possible conversion of the CEN/TS into an EN is reached

11、.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Polan

12、d, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.English VersionCEN/TS 17158:2018 (E)European foreword 3Introduction . 41 Scope .52 Normative references 53 Principle 54 Apparatus .54.1 Vibrating sieve analysis . 54.2 Air jet sieve analysis . 54.

13、3 Static image analysis systems 64.4 Dynamic image analysis systems using automatic dispersion by jet air and image acquisition with a CMOS-camera 65 Calibration 65.1 Vibrating sieve analysis . 65.2 Air jet sieve analysis . 65.3 Static image analysis systems 65.4 Dynamic image analysis systems 66 Pr

14、ocedure.76.1 Sampling and preparation of test specimens . 76.1.1 General 76.1.2 Vibrating sieve analysis 76.1.3 Air jet sieve analysis 76.1.4 Static image analysis systems . 76.1.5 Dynamic image analysis systems . 76.2 Observation and measurement 76.2.1 Vibrating sieve analysis 76.2.2 Air jet sieve

15、analysis 76.2.3 Static image analysis systems . 86.2.4 Dynamic image analysis systems . 86.3 Expression of results 86.3.1 Vibrating sieve analysis 86.3.2 Air jet sieve analysis 86.3.3 Static image analysis systems . 86.3.4 Dynamic image analysis systems . 86.4 Test report . 96.4.1 Vibrating sieve an

16、alysis 96.4.2 Air jet sieve analysis 96.4.3 Static image analysis systems . 96.4.4 Dynamic image analysis systems . 9Bibliography .102Contents PagePD CEN/TS 17158:2018CEN/TS 17158:2018 (E)European forewordThis document (CEN/TS 17158:2018) has been prepared by Technical Committee CEN/TC 249 “Plastics

17、”, the secretariat of which is held by NBN.Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN shall not be held responsible for identifying any or all such patent rights.According to the CEN/CENELEC Internal Regulations, the nati

18、onal standards organisations of the following countries are bound to announce this Technical Specification: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia

19、, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.3PD CEN/TS 17158:2018CEN/TS 17158:2018 (E)IntroductionEither optical systems or sieve analysis can be used for the determination of pa

20、rticle size of wood flour or flour based on alternative lignocellulosic materials for use in wood plastic composites. Microscopic analysis is also possible but requires a significant amount of time and effort to generate statistically viable results, hence, it is not suggested for this task. Particl

21、e size determination can be performed using raw material as well as processed and extracted material to observe the effects of processing on particle size. Optical systems and in addition, sieve analysis can be performed using a vibrating sieve or an air-jet sieve in order to match results from opti

22、cal measurements with those from mechanical measurements and which are suitable to determine the mass of particles which are too fine or too coarse. Sieve analysis does not generate any information regarding the shape of the particles and leads only to a diameter-based, coarse size distribution. The

23、refore, size parameters supplied by optical measurements cannot directly be compared with those from sieve analysis. Methods using active air-jet dispersion are particularly suitable for material containing long natural fibres which tend to agglomerate. Optical methods derive very similar results re

24、garding the type of distribution and its characteristic percentiles for the particle length and a shape factor (length/width ratio) if optical resolution and weighting method are comparable. For a comparison between these measurement principles see (Plinke et. al 2016 2).This document is related to

25、the determination of particle size of the lignocellulosic material used in the preparation of wood-polymer composites according to EN 15534-1 and prEN 15534-2 for compounds. Furthermore, the methods mentioned in this document can be used to determine the extent of particle degradation after processi

26、ng, i.e. after compounding and/or extrusion and injection-moulding. Manufacturers of wood and other natural fibre producers and users of wood and natural fibres can use the methods described in this document to determine particle size of their lignocellulosic raw materials and to compare the particl

27、e size of their raw materials to alternative lignocellulosics. There are no requirements for particle size of the lignocellulosic fillers used in WPC, however, it is useful to know particle size for formulation development and to understand the relationship between particle size and WPC properties s

28、uch as strength, water uptake and swelling.4PD CEN/TS 17158:2018CEN/TS 17158:2018 (E)1 ScopeThis document specifies mechanical and optical test methods for the determination of particle size of lignocellulosic material for use in wood plastic composites (WPC) and natural fibre composites (NFC).2 Nor

29、mative referencesThe following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any a

30、mendments) applies.EN ISO 4610, Plastics Vinyl chloride homopolymer and copolymer resins Sieve analysis using air-jet sieve apparatus (ISO 4610)ISO 9276-6:2008, Representation of results of particle size analysis Part 6: Descriptive and quantitative representation of particle shape and morphologyISO

31、 13322-2, Particle size analysis Image analysis methods Part 2: Dynamic image analysis methodsDIN 66165-1:2016, Particle size analysis Sieving analysis Part 1: FundamentalsDIN 66165-2:2016, Particle size analysis Sieving analysis Part 2: Procedure3 PrincipleThe determination of particle size is carr

32、ied out either mechanically using the vibrating sieve analysis; or the air jet sieve analysis; or optically based on automatic image analysis systems after manual dispersion on transparent foil and image acquisition using a flat-bed scanner (designated here as “static image analysis system”); or aft

33、er automatic dispersion by jet air and image acquisition using a CMOS-camera (designated here as “dynamic image analysis system”).4 Apparatus4.1 Vibrating sieve analysisThe vibrating sieve analysis is carried out according to DIN 66165-1:2016, procedure F (vibrating screen in static air).The number

34、and opening widths of the sieve inserts shall be suitable for the material under investigation. It is recommended that this apparatus is used for an expected size range between 100 m and 20 000 m (particle length) and for material which does not tend to agglomerate. The opening widths of the sieve i

35、nserts shall be chosen from DIN 66165-1:2016, Table 2 so that the expected size range is covered.4.2 Air jet sieve analysisThe air jet sieve analysis is carried out according to EN ISO 4610.The number and opening widths of the sieve inserts shall be suitable for the material under investigation. It

36、is recommended that this apparatus is used for an expected size range between 20 m and 2 000 m 5PD CEN/TS 17158:2018CEN/TS 17158:2018 (E)(particle length). The opening widths of the sieve inserts shall be chosen from DIN 66165-1:2016, Table 2 so that the expected size range is covered.4.3 Static ima

37、ge analysis systemsAn automatic image analysis system with evaluation software after manual dispersion on transparent foil and picture recording with flat-bed scanner using a flat-bed scanner with transparency unit and an automatic feeder1).NOTE Product versions without feeder are less suitable due

38、to material handling.4.4 Dynamic image analysis systems using automatic dispersion by jet air and image acquisition with a CMOS-cameraAn automatic image analysis system with evaluation software after automatic dispersion by jet air using a dry disperser and a vibratory feeder and picture recording w

39、ith a CMOS-camera2).5 Calibration5.1 Vibrating sieve analysisNo calibration is necessary if the manufacturers recommendations for operation are met.5.2 Air jet sieve analysisNo calibration is necessary if the manufacturers recommendations for operation are met.5.3 Static image analysis systemsPerfor

40、m a scanner test and calibrate the system with respect to image quality and gray value thresholds according to the manufacturers instructions, using a set of spheres with a uniform diameter of 600 m. No more calibration is necessary for the scanners geometry. It is recommended to frequently verify t

41、he measurement and evaluation chain using synthetic flock fibres with a known and narrow length distribution (see Fischer et al. 2016 3).5.4 Dynamic image analysis systemsCalibrate the system using a suitable reference material in order to verify the accuracy of the measurement. Verify the threshold

42、 values and optical sensors of the system. Calibrate, verify, and clean the system as frequently as necessary.1) The product “FibreShape” (manufacturer: IST Ag, Vilters, Switzerland) in the version FibreShape Basic Automatic (using a flat-bed scanner with transparency unit and an automatic feeder) t

43、ogether with evaluation software supplied by the manufacturer is an example of a suitable product available commercially. This information is given for the convenience of users of this European Standard and does not constitute an endorsement by CEN of this product.2) The product “QICPIC” (manufactur

44、ed by Sympatec, Clausthal, Germany) with dry disperser “RODOS/L” and vibratory feeder “VIBRI/L” together with evaluation software supplied by the manufacturer is an example of a suitable product available commercially. This information is given for the convenience of users of this European Standard

45、and does not constitute an endorsement by CEN of this product.6 PD CEN/TS 17158:2018CEN/TS 17158:2018 (E)6 Procedure6.1 Sampling and preparation of test specimens6.1.1 GeneralFor all methods the sample has to be dry. For most materials mechanical sub-sampling is not possible. Therefore, the operator

46、 has to ensure that the sample is representative of the material. If the result appears questionable it is recommended to perform three measurements with independently drawn samples.6.1.2 Vibrating sieve analysisPerform the measurement according to DIN 66165-2. It is recommended to use an initial ma

47、ss of at least 50 g.6.1.3 Air jet sieve analysisPerform the measurement according to EN ISO 4610, but in one run for each sieve insert. It is recommended to use an initial mass of at least 50 g. Start with the sieve insert with the smallest opening width, and determine the mass of the throughput fra

48、ction from the difference between the initial weight and the sieve retention. Repeat the procedure with the sieve retention for each fraction to be determined.6.1.4 Static image analysis systemsUse a parameter set for measurement with maximum resolution but activate the option to exclude agglomerati

49、ons. Disperse an appropriate quantity of particles manually on the foil of the sample feeder using a hand sieve with appropriate opening width. Make sure that that the area coverage of particles on the image field does not exceed ca. 2 %. If the material tends to agglomerate, those agglomerations cannot be avoided totally but try to minimize them as much as possible. Set the automatic sample feeding option to three image fields and start the measurement.6.1.5 Dynamic image analysis systemsDisperse an appropriate quantity of particles o