1、PD 6699-1:2007 Nanotechnologies Part 1: Good practice guide for specifying manufactured nanomaterials ICS 71.100.99 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW PUBLISHED DOCUMENTPublishing and copyright information The BSI copyright notice displayed in this document indica
2、tes when the document was last issued. BSI 2007 ISBN 978 0 580 58723 8 The following BSI references relate to the work on this Published Document: Committee reference NT/1 Publication history First published December 2007 Amendments issued since publication Amd. no. Date Text affected PD 6699-1:2007
3、 BSI 2007 i PD 6699-1:2007 Contents Foreword ii Introduction 1 1 Scope 2 2 Terms and definitions 2 3 Specifying manufactured nanomaterials having all three dimensions at the nanoscale, i.e. nanopowders 2 4 Specifying manufactured nanomaterials having two dimensions at the nanoscale carbon nanotubes
4、3 5 Specifying other manufactured nanomaterials with two dimensions at the nanoscale, i.e. nanofibres and nanorods 4 6 Specifying manufactured nanomaterials having only one dimension at the nanoscale, i.e. nanoscale thin films or coatings 5 7 Recommended measurement methods for determining the chara
5、cteristics of manufactured nanomaterials identified as important for specification purposes 6 8 Possible impacts of contamination on the properties and performance of manufactured nanomaterials and their mitigation 13 9 Packaging, labelling and transport 13 Bibliography 15 List of tables Table 1 Mea
6、surement methods for batch quality control 6 Table 2 Measurement methods for audit check purposes 9 Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 16, an inside back cover and a back cover.PD 6699-1:2007 ii BSI 2007 Foreword Publishing infor
7、mation This Published Document is published by BSI and came into effect on 31 December 2007. BSI Committee NTI/1, Nanotechnologies, takes collective responsibility for its preparation. The Committee wishes to acknowledge the contribution of Powdermatrix. A list of organizations represented on the Co
8、mmittee can be obtained on request to its secretary. This Published Document was commissioned by the UK Department for Innovation, Universities and Skills (DIUS) to provide guidance for manufacturers and users of nanomaterials on the preparation of comprehensive technical specifications to help ensu
9、re reproducibility of delivered product properties. Use of this document As a guide, this Published Document takes the form of guidance and recommendations. It should not be quoted as if it were a specification and particular care should be taken to ensure that claims of compliance are not misleadin
10、g. It has been assumed in the preparation of this Published Document that the execution of its provisions will be entrusted to appropriately qualified and experienced people, for whose use it has been produced. Presentational conventions The provisions in this Published Document are presented in rom
11、an (i.e. upright) type. Its recommendations are expressed in sentences in which the principal auxiliary verb is “should”. The word “may” is used in the text to express permissibility, e.g. as an alternative to the primary recommendation of the clause. The word “can” is used to express possibility, e
12、.g. a consequence of an action or an event. Contractual and legal considerations This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. This Published Document is not to be regarded as a British Standard. BSI 2007 1
13、 PD 6699-1:2007 Introduction The need for this guide arises from experience that, on occasions, agreed specifications between suppliers and users of manufactured nanomaterials have failed to ensure delivery of material, on a batch-to-batch basis, that responds consistently to downstream processing a
14、nd/or generates consistent performance in the final product. This observed inconsistent performance of batches of material, all apparently “in specification”, has led to the conclusion that the cause has to be related to one or more of the following. a) The specification agreed between user and supp
15、lier does not cover all material characteristics that have an influence on performance and/or processability or has been interpreted differently by the user and supplier. b) One or more material characteristic is currently being measured by an inappropriate technique. c) One or more measurement tech
16、nique is being applied in an incorrect manner. This guide is intended to address all of these issues. Each broad category of manufactured nanomaterial has been considered in a separate clause; those at the nanoscale in all three dimensions, those at the nanoscale in two dimensions and those at the n
17、anoscale in one dimension. As the most significant subset of two-dimensional nanomaterials, carbon nanotubes have been considered separately to other examples such as nanorods or nanofibres. Through a process of discussion with an expert consultative group, for each category of manufactured nanomate
18、rial: a list has been compiled of material characteristics believed to have a definite influence on product performance and/or downstream processing in all areas of application and which have therefore to be controlled in order to achieve product consistency; further material characteristics have be
19、en identified, which have a definite influence in certain areas of application; where the inclusion of all of these material characteristics in agreed specifications still does not ensure batch-to-batch consistency, a further list of characteristics is provided which could be investigated; for all i
20、dentified material characteristics, appropriate measurement methods are recommended, which separate into two categories: those generally utilizing relatively low-cost equipment, which can be envisaged for use in routine batch quality control in an industrial environment, and those which require expe
21、nsive equipment and which might therefore only be viable for use in less frequent audit checks; a brief description of the basis of each measurement method is provided and, wherever possible, reference is made to an appropriate source of guidance on best practice in carrying out the test (usually an
22、 established standard); and where no viable or validated measurement method can currently be identified, this is also stated.PD 6699-1:2007 2 BSI 2007 1 Scope This Published Document provides guidance on the preparation of comprehensive technical specifications for manufactured nanomaterials in orde
23、r to ensure the delivery of product that behaves in a reproducible manner. The document includes guidance on specifying the physical and chemical characteristics of manufactured nanomaterials, which might affect performance or subsequent processing. This document does not include guidance on specify
24、ing the health and safety characteristics of manufactured nanomaterials, nor does it include guidance on specifying bulk materials containing nanosized phases. 2 Terms and definitions For the purposes of this Published Document, the terms and definitions given in PAS 136 apply. 3 Specifying manufact
25、ured nanomaterials having all three dimensions at the nanoscale, i.e. nanopowders 3.1 Material characteristics with a definite influence on product performance and/or downstream processability The following characteristics are essential in specifying manufactured nanopowders in all areas of applicat
26、ion. Particle size distribution. Crystallite size distribution. Degree of agglomeration. Specific surface area. Bulk chemical composition. 3.2 Additional characteristics that have a definite influence in specific areas of application Where manufactured nanopowders are to be used in specific areas of
27、 application, it will be essential to specify the following additional characteristics. Dispersibility in solid matrices in specifying nanoscale reinforcements in composite materials. Dispersibility in liquids polar and non-polar. Fuchs surface area use of nanoparticles in aerosols. Composition acro
28、ss the particle cross-section particles with a core shell structure. BSI 2007 3 PD 6699-1:2007 3.3 Other material characteristics with a possible influence on product performance and/or downstream processability To ensure reproducible behaviour in processing and consistent product performance, it mi
29、ght be necessary to specify other characteristics from the following list. Particle morphology. Flow characteristics. T a p d e n s i t y . A p p a r e n t d e n s i t y . Porosity. Surface chemical composition. Crystal structure. Moisture content. p H . C o l o u r . Transparency. 4 Specifying manu
30、factured nanomaterials having two dimensions at the nanoscale carbon nanotubes 4.1 General Carbon nanotubes have been identified as the most commercially significant example of nanomaterials with two dimensions at the nanoscale. For this reason, this clause is dedicated specifically to carbon nanotu
31、bes. Other types of two-dimensional nanomaterials are addressed in Clause 5. 4.2 Material characteristics with a definite influence on product performance and/or downstream processability The following characteristics are essential in specifying carbon nanotubes in all areas of application. Length d
32、istribution. D i a m e t e r d i s t r i b u t i o n . Aspect ratio distribution. Wall thickness. Number of walls, i.e. single-walled, double-walled, or multi-walled. Chemical purity presence of catalyst. Structural/Product purity presence of other carbon-based materials.PD 6699-1:2007 4 BSI 2007 4.
33、3 Additional characteristics that have a definite influence in specific areas of application Where nanotubes are to be used in specific areas of application, it will be essential to specify the following additional characteristic. Symmetry for electrical properties. 4.4 Other material characteristic
34、s with a possible influence on product performance and/or downstream processability To ensure reproducible behaviour in processing and consistent product performance, it might be necessary to specify other characteristics from the following list. Dispersibility. Degree of agglomeration. Surface chem
35、ical analysis. Surface functionalization. Structure at the ends, i.e. open or closed. 5 Specifying other manufactured nanomaterials with two dimensions at the nanoscale, i.e. nanofibres and nanorods 5.1 Materials characteristics with a definite influence on product performance and/or downstream proc
36、essability The following characteristics are essential in specifying manufactured nanofibres or nanorods in all areas of application. Size distribution. Length distribution. Diameter distribution. Aspect ratio distribution. Degree of agglomeration. Surface area. P o r o s i t y . Bulk chemical analy
37、sis. 5.2 Additional characteristics that have a definite influence in specific areas of application Where nanofibres and nanorods are to be used in specific areas of application, it will be essential to specify the following additional characteristics. BSI 2007 5 PD 6699-1:2007 Dispersibility in sol
38、id matrices in specifying nanoscale reinforcements for composites. Strength of the interface with the matrix in specifying nanoscale reinforcements for composites. Crystallographic and mechanical anisotropy. 5.3 Other material characteristics with a possible influence on product performance and/or d
39、ownstream processability To ensure reproducible behaviour in processing and consistent product performance, it might be necessary to specify other characteristics from the following list. Compatibility with matrices. Dispersibility in liquid. Flow characteristics. Surface chemical analysis. Surface
40、functionalization. 6 Specifying manufactured nanomaterials having only one dimension at the nanoscale, i.e. nanoscale thin films or coatings 6.1 General The control of quality of nanoscale coatings is best achieved by defining optimum coating process conditions, initially by the measurement of agree
41、d characteristics of the coating. Batch-to-batch control of coating quality is then achieved by monitoring and control of process conditions rather than by routine measurement of coating characteristics. The characteristics listed in 6.2 and 6.3 are those which should be considered in the initial de
42、finition of coating conditions. Relevant measurement methods for coating characteristics are therefore listed in Table 2 rather than Table 1. 6.2 Material characteristics with a definite influence on product performance The following characteristics are essential in defining process conditions for t
43、he control of quality of nanoscale coatings. Coating thickness. T h i c k n e s s u n i f o r m i t y . Chemical composition of the coating. Interfacial strength with the substrate.PD 6699-1:2007 6 BSI 2007 6.3 Other material characteristics with a possible influence on product performance and/or do
44、wnstream processability To ensure consistent product performance from nanoscale coatings, it might be necessary to consider other characteristics from the following list. P o r o s i t y . Surface chemical composition. 7 Recommended measurement methods for determining the characteristics of manufact
45、ured nanomaterials identified as important for specification purposes Appropriate measurement methods separate into two categories: those generally utilizing relatively low-cost equipment for use in routine batch quality control in an industrial environment (see Table 1), and those which require exp
46、ensive equipment and which might therefore only be viable for use in less frequent audit checks (see Table 2). Sampling of powders should be carried out according to BS 3406-1. As many nanomaterials are reactive, their physical and chemical properties can be affected by the sampling point and their
47、storage environment. Consequently, supplier and purchaser should agree the sampling point and storage of the samples for comparability of results. Table 1 Measurement methods for batch quality control Metric Method Guidance 1. Particle size distribution Different measuring techniques might yield dif
48、ferent results for the same material batch. In specifying the material, supplier and purchaser should agree the technique used to measure the particle size distribution. Light scattering methods Applicable for particle diameters greater than about 40 nm, depending on the nature of the particle. Cali
49、bration of the equipment and measurement procedure should be in accordance with BS ISO 13320-1 or BS ISO 21501-2. Electron microscopy and image analysis Guidelines for the calibration of image magnification can be found in BS ISO 16700. Guidance on static image analysis methods is available in BS ISO 13322-1. Electrokinetic sonic amplitude testing A variant of zeta potential testing, in which an alternating voltage is applied to
