SEMINAR: UPDATES ON SMR AND SMR LABORATORY INTEGRATION SYSTEM (SLIS)

REVISED TEST METHOD :DETERMINATION OF ASH

Scope

Principle

Apparatus

Procedure

Expression of Result

Outline

Differences between previous & revised test method

PREVIOUS TEST METHOD REVISED TEST METHOD

• Explanatory notes• Apparatus and

Materials• Procedure• Calculation

• Scope• Principle• Apparatus • Procedure• Expression of result• Precision• Test report

Scope

This part of SMR Bulletin No.7 specifies a method for the determination of ash from raw natural rubbers.

Principle

Explanatory notes

A weighed test piece is wrapped in ashless filter paper, followed by incineration in a muffle furnace at about 550 °C ± 25 °C for two to four hours until all the carbonaceous matter has been burnt off and constant mass is attained.

Apparatus

CrucibleMuffle furnace

Ashlessfilter paper

Desiccator Tong

Procedure

Weigh 5 g to 10 g test piece of the homogenisedrubber

Wrap in ashlessfilter paper and place in a crucible

Introduce the crucible into a muffle furnace

(550 °C ± 25 °C ,

2 h to 4 h)

Cool the crucible in a desiccator and then weigh

Expression of Result

Where

A is the mass, in grams, of the crucible and ash;

B is the mass, in grams, of the empty crucible; and

C is the mass, in grams, of the test piece.

100(%)

C

BAAsh

Expression of Result

TEST METHODS CALCULATION

SMR BULLETIN NO.7

ISO 247 (METHOD A & B)

(NEWLY PROPOSED METHOD C BY MALAYSIA)100(%)

C

BAAsh

100(%)

C

DBAAsh

Where A is the mass, in grams, of the crucible and ash;B is the mass, in grams, of the empty crucible; C is the mass, in grams, of the test piece; andD is the mass, in grams, of the ash from filter paper.

ISO 247

TEST METHODS SCOPES

AShall not be used for the determination of ash from raw, compounded or vulcanized rubbers containing chlorine, bromine or iodine

BShall be used for compounded or vulcanized rubbers containing chlorine, bromine or iodine. It shall not be used for uncompounded rubbers

C

Intended to be used for the determination of ash from raw, compounded or vulcanized rubber not containing chlorine, bromine or iodine by wrapping the test portion in ashlessfilter paper

Proposed Lab Works to resolve the comments on calculation

• 1st Lab Work

• 2nd Lab Work

Lab Work 1

Ashing all raw rubber samples, including control (w/o filter paper) and wrapped samples (by using 3 different brands of filter paper) together in one furnace to eliminate uncertainties due to temperature, human and variation in days and time if any that could have affected the results.

Filter papers employed in the studies

• DR

• NICE

• W

CALCULATION OF ASH BY USING FEW FORMULAS

Aim: To observe the closest value of ash to the control value

Control (Without Fi l ter

Paper) From Worksheet

Control to be done

SMR BULLETIN NO.7 ISO 247

DR 0.3224 0.3319

NICE 0.3340 0.3450

W 0.3244 0.3354

0.3269 0.3374

DR 0.3303 0.3395

NICE 0.3123 0.3230

W 0.3264 0.3374

0.3230 0.3333

DR 0.3601 0.3689

NICE 0.3549 0.3658

W 0.3636 0.3744

0.3596 0.3697

DR 0.3562 0.3652

NICE 0.3513 0.3617

W 0.3535 0.3640

0.3537 0.3637AVERAGE

270916 (am) 0.36240.0087 0.0013

AVERAGE

270916 (pm) 0.36780.0082 0.0019

AVERAGE

041016 (am) 0.33920.0162 0.0059

041016 (pm) 0.33620.0092 0.0013

AVERAGE

Date Brands Diff. Di ff.

Lab Work 2

Ashing all the raw rubber samples, including control (w/o filter paper) and wrapped samples together in one furnace but using different amount of filter papers to wrap the samples. This is to confirm that regardless of the numbers of filter paper used; the percent ratio of ash from filter paper to the weight of filter paper will remain the same.

CALCULATION OF ASH BY USING FEW FORMULAS

Aim: To observe the closest value of ash to the control value

Control (Without Fi l ter

Paper) From Worksheet

Control to be done

SMR BULLETIN NO.7 ISO 247

W (1) 0.3396 0.3503

W (2) 0.3411 0.3517

W (3) 0.3351 0.3473

0.3386 0.3498

W (1) 0.3453 0.3562

W (2) 0.3521 0.3631

W (3) 0.3478 0.3605

0.3484 0.3599

NICE (1) 0.3551 0.3657

NICE (2) 0.3596 0.3705

NICE (3) 0.3554 0.3699

0.3567 0.3687

NICE (1) 0.3425 0.3530

NICE (2) 0.3398 0.3504

NICE (3) 0.3421 0.3568

0.3415 0.3534

DR (1) 0.3464 0.3535

DR (2) 0.3430 0.3520

DR (3) 0.3428 0.3535

0.3441 0.3530

DR (1) 0.3535 0.3606

DR (2) 0.3482 0.3570

DR (3) 0.3454 0.3560

0.3490 0.3579

0.0083

0.0130

0.0005

0.0041

0.0007

0.0041

0.0006

0.0115

0.0161

Diff.

0.0072 0.00400.3458

0.3593

0.3682

0.3575

Diff.

0.0109

Sample IDDate

061016

280916

051016

AVERAGE

0.3523

0.3620

AVERAGE

AVERAGE

AVERAGE

AVERAGE

AVERAGE

290916

051016

280916

OBSERVATION

1) From Lab work 1, results for ISO 247 formula are closer tothe control values. The filter paper was not affectingsignificantly the ash content of the rubber samples.

2) Lab Work 2 is supporting the earlier observation whereresults of Ash following ISO 247 formula are closer to thecontrol values.

Based on the observation, it is proposed for ash test method in SMR Bulletin No. 7 to use the same

formula as ISO 247.

CONCLUSION

THANK YOU

for your

ATTENTION