1、BRITISH STANDARD BS 5131-1.2: 1991 Methods of test for Footwear and footwear materials Part 1: Adhesives Section 1.2 Resistance of adhesive joints to peeling NOTEIt is recommended that this Section should be read in conjunction with BS5131-0, published separately.BS5131-1.2:1991 This British Standar
2、d, having been prepared under the directionof the Textiles and Clothing Standards Policy Committee, was published underthe authority of the Standards Board and comes into effect on 30April1991 BSI 10-1999 First published as BS 5131-1.1.2 August 1976 Second edition April 1991 The following BSI refere
3、nces relate to the work on this standard: Committee reference TCM/39 Draft for comment 89/36217 DC ISBN 0 580 19189 3 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Textiles and Clothing Standards Policy Committee (TCM/-) to Technical C
4、ommittee TCM/39, upon which the following bodies were represented: British Footwear Manufacturers Federation British Leather Confederation British Rubber Manufacturers Association British Steel plc Consumer Standards Advisory Committee of BSI Cork Industry Federation Footwear Components Federation F
5、ootwear Distributors Federation Institute of Trading Standards Administration Iron and Steel Trades Confederation Lancashire Footwear Manufacturers Association Mail Order Traders Association of Great Britain Ministry of Defence National Union of Footwear, Leather and Allied Trades Office of Fair Tra
6、ding SATRA Footwear Technology Centre The following bodies were also represented in the drafting of the standard, through subcommittees and panels: British Adhesives and Sealants Association British Paper and Board Industry Federation British Plastics Federation Multiple Shoe Retailers Association R
7、APRA Technology Ltd. Amendments issued since publication Amd. No. Date CommentsBS5131-1.2:1991 BSI 10-1999 i Contents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 Principle 1 3 Apparatus 1 4 Preparation and bonding of test assemblies 1 5 Conditioning 1 6 Cutting of test spe
8、cimens 1 7 Procedure 2 8 Additional tests 6 9 Expression of results 6 10 Test report 7 Figure 1 Test specimen (cut from test assembly prepared as describedinBS5131-1.3 or prepared by indirect bonding as described in BS 5131-1.7) 2 Figure 2 Test assembly prepared by direct bonding as described in BS
9、5131-1.7 3 Figure 3 Test specimen (cut from test assembly prepared by directbondingasdescribed in BS 5131-1.7) 4 Figure 4 Types of bond failure 5 Figure 5 Example of a typical graph of peeling force against extensionwhichincludes an initial peak 6 Publication(s) referred to Inside back coverBS5131-1
10、.2:1991 ii BSI 10-1999 Foreword This Section of BS 5131 has been prepared under the direction of the Textiles and Clothing Standards Policy Committee. It supersedes BS5131-1.1.2:1976, which is withdrawn. A British Standard does not purport to include all the necessary provisions of a contract. Users
11、 of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1 to8, an inside back cover and a back
12、cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS5131-1.2:1991 BSI 10-1999 1 1 Scope This Section of BS5131 describes a method for measuring the strength, in terms of resista
13、nce to peeling, of a bond between two sheet materials that have been bonded together. The method is applicable to a great variety of combinations of upper materials, soling materials and adhesives, where at least one of the adherends is flexible. NOTE 1The purpose of the method is to test joints rat
14、her than to compare adhesives. As a consequence, unlike BS5131-1.1, no recommendations are given concerning appropriate adherends. In BS5131-1.1 the two adherends are subjected to a constant separating force, and therefore in principle the test specimen may remain intact. In this Section, the two ad
15、herends are pulled apart at a constant rate; the test specimen will inevitably fail, and it is the forces required to cause the test specimen to fail and the nature of the failure that are under investigation. This test is more destructive in its philosophy than the test described in BS5131-1.1. In
16、BS5131-1.1 the failures (e.g. cohesive failure of the adhesive layer, or failure of adhesion to one adherend) are associated with the adhesive. In this Section, however, alternative types of failure which may take place within the adherend are described. NOTE 2For the peel bond strength of specimens
17、 cut from made-up footwear see BS5131-5.4. NOTE 3The titles of the publications referred to in this standard are listed on the inside back cover. 2 Principle The two adherends of a bonded assembly are peeled apart by forces acting at an angle of180 to each other. The peel angle depends on the flexib
18、ility of the adherends. The peeling force is recorded continuously and the mean peeling force is calculated. 3 Apparatus 1) 3.1 Conditioning cabinet or room, maintaining an atmosphere at a preferred condition of20 2 C and652% r.h., or an allowed condition of23 2 C and505% r.h. NOTEThe conditioning a
19、tmosphere for footwear and footwear materials is normally20 C and65% r.h., whereas the conditioning atmosphere for adhesives is normally23 C and50% r.h. 3.2 Tensile testing machine, of low inertia, with a constant rate of extension, with continuous recording and with a jaw separation rate of100 20mm
20、/min. 3.3 Cutting device, suitable for cutting test assemblies into test specimens, which neither compresses nor tends to split the layers of the test assembly at the edges produced by cutting. NOTEA rotary disc cutter or a sharp hand knife, for example, is a suitable tool. A press knife is not suit
21、able because of the large compression force that it applies to the test assembly. 4 Preparation and bonding of test assemblies Prepare the materials and bond the test assemblies, incorporating a paper or tape insert, as described in BS5131-1.7 for hot melt adhesive bonds and as described in BS5131-1
22、.3 for all other types of bond. Produce test assemblies of sufficient size and number so as to enable four or eight test specimens (see clauses5 and8) to be prepared. 5 Conditioning Between bonding the test assemblies and cutting them into test specimens, store the test assemblies in the conditionin
23、g cabinet or room (3.1). In cases where it is known that the bond is formed rapidly within a short period of time, after which there is no change in the bond, condition one set of test assemblies for a period of484h. In other cases, condition one set of test assemblies for a period of48 4h and a sec
24、ond set of test assemblies for a period of14 2 days so that any change in bond strength due to changes in the adhesive (e.g.increased curing or crystallization) may be assessed. NOTEBy determining the bond strength after various conditioning periods, any change in the bond strength due to changes in
25、 the adhesive (e.g. increased curing or crystallization) may be assessed. 6 Cutting of test specimens At the end of the conditioning period (see clause5), cut one set of test assemblies into four test specimens using the cutting device (3.3) as follows. a) Where the test assemblies have been prepare
26、d as described in BS5131-1.3 or prepared by indirect bonding as described in BS5131-1.7, cut test specimens30.0 0.5mm by approximately50mm, discarding two marginal strips approximately5mm wide if the test assemblies are approximately70mm wide. A test specimen is shown inFigure 1. b) Where the test a
27、ssemblies have been prepared by indirect bonding as described in BS5131-1.7, cut test specimens as in itema) (preferred) and illustrated inFigure 1, or cut test specimens20.0 0.5mm by approximately50mm (allowed). NOTERecent developments relating to indirect bonding using hot melt adhesives are such
28、that in some cases it may be difficult or inconvenient to prepare test assemblies wide enough to produce test specimens30mm wide. In such cases, the allowed test specimen is as illustrated inFigure 1 except that the width is20.0 0.5mm instead of30.0 0.5mm. 1) For information on the availability of s
29、uitable apparatus to perform this test, apply to Enquiry Section, BSI, Linford Wood, Milton Keynes, MK146LE, quoting the number of this standard and the clause number referring to the items concerned. Enclose a stamped addressed envelope for reply.BS5131-1.2:1991 2 BSI 10-1999 c) Where the test asse
30、mblies have been prepared by direct bonding as described in BS5131-1.7, cuteach test assembly along the line AB as shown inFigure 2 to produce test specimens20.0 0.5mm by approximately65mm, as shown inFigure 3. 7 Procedure 7.1 Separate by hand the two adherends at the end of a test specimen where th
31、e paper or tape is inserted so as to produce two free adherend legs. Clamp one leg in each jaw of the tensile testing machine (3.2). Operate the tensile testing machine at a jaw separation rate of100 20mm/min until the jaws are separated by a distance of at least30mm, using the recording mechanism t
32、o provide a graph of the peeling load against extension. If the graph has an initial peak, as illustrated inFigure 5 examine the small area of the test specimen at which separation commenced. Examine the remaining area produced by separation, noting the type(s) of failure and the percentage of the t
33、otal peeled area over which each type of bond failure has occurred. NOTE 1Types of bond failure are illustrated inFigure 4 and may be classified as follows: a) failure of adhesion to either adherend material; b) failure of surface layer of adherend material; c) deep failure of adherend material (con
34、tinuous failure); d) deep failure of adherend material (“leg” tore off); e) cohesive failure of adhesive; f) non-coalescence of adhesive films. Where the test specimens have been prepared by direct bonding using hot melt adhesives as described in BS5131-1.7, check that the adhesive coverage on the a
35、reas of each test specimen after peeling is not less than95%. If this is not the case, reject the test results, prepare additional test specimens from additional test assemblies, and repeat the test until sufficient test results from acceptable test specimens are obtained. NOTE 2In direct bonding of
36、 hot melt adhesives, as described in BS5131-1.7, the assembly is closed and bonded immediately after the application of adhesive (which is applied as a molten ribbon). The technique of application and the short open time result in a situation where it is difficult for the operator to ensure complete
37、 adhesive coverage. This problem does not arise where test assemblies have been prepared by the indirect bonding of hot melt adhesives as described in BS5131-1.7 or by the methods given in BS5131-1.3. 7.2 Test the remaining three test specimens by the procedure described in7.1. Figure 1 Test specime
38、n (cut from test assembly prepared as described in BS5131-1.3 orprepared by indirect bonding as described in BS5131-1.7)BS5131-1.2:1991 BSI 10-1999 3 7.3 Where it is not known that the bond is formed rapidly within a short period of time (see clause5), at the end of the second conditioning period cu
39、t the second set of test assemblies into four test specimens, as described in clause6, using a suitable cutting device (3.3) and repeat the procedure described in7.1 and7.2. Figure 2 Test assembly prepared by direct bonding as described in BS5131-1.7BS5131-1.2:1991 4 BSI 10-1999 Figure 3 Test specim
40、en (cut from test assembly prepared by direct bonding as describedinBS5131-1.7)BS5131-1.2:1991 BSI 10-1999 5 Failure of adhesion to either adherend material Adhesion to upper Adhesion to sole Failure of surface layer of adherend material Surface of upper Surface of sole Deep failure of adherend mate
41、rial (continuous failure) Deep failure within upper Deep failure within sole Deep failure of adherend material (“leg” tore off) Deep failure of upper Deep failure of sole Cohesive failure of adhesive Non-coalescence of adhesive films Figure 4 Types of bond failure (see 7.1)BS5131-1.2:1991 6 BSI 10-1
42、999 8 Additional tests Where one of the adherend materials (e.g. cellulose board insoles, polyurethane (PU) coated fabric uppers) exhibits directional properties, regard each of the following three directions as a different test condition: a) in the machine direction and with the run of the sheet; b
43、) in the machine direction and against the run of the sheet; c) in the cross direction. In such cases, prepare a set of four test specimens in each of the three directions, and carry out the procedure described in7.1 and7.2 on each of these three sets; where it is not known that the bond is formed r
44、apidly within a short period of time (see7.3), prepare a further set of four test specimens in each of these three directions and carry out the procedure described in7.3. 9 Expression of results 9.1 Estimate the mean peeling force for each test specimen from the graph of the peeling force against ex
45、tension by using a superimposed grid or by any other suitable means, excluding from the estimation of the mean any initial peak force. NOTEAn example is given inFigure 5. 9.2 If the type of failure is the same for each test specimen, calculate the arithmetic mean of the four mean peeling forces. Div
46、ide this value by the width of the test specimen and express the result, in newtons per millimetre (kilograms force per centimetre), as the bond strength of the bonded assembly. 9.3 If the type of failure is not the same for each test specimen, calculate the bond strength as described in9.2 for each
47、 type of failure observed. Figure 5 Example of a typical graph of peeling force against extension which includesaninitial peakBS5131-1.2:1991 BSI 10-1999 7 9.4 If the graph of the peeling force against extension shows an initial peak force record this for each test specimen. If it is evident that th
48、e initial peak force is caused by initial breaking through the adhesive rather than breaking through a surface layer of an adherend (e.g. the plastics layer of a plastics-coated fabric), ignore the initial peak force because this is due to the particular form of the test specimen and would not occur
49、 in a production item. If the type of failure is the same for each test specimen, calculate the mean initial peak force of the four test specimens and express this in newtons per millimetre (kilograms force per centimetre). If the type of failure is not the same for each specimen calculate the mean initial peak force in newtons per millimetre (kilograms force per centimetre) for each type of failure observed. 10 Test Report The test report shall include the following items: a) results, expressed in accordance with clause9;
