99 Preparation of expandable graphite and flameretardant properties

弘光科技大學 ( 學院) 99學年度學生專題研究競賽 Preparation of expandable graphite and flame-retardant properties of its halogen-free flame-retardant HDPE composites Tai-Ying Liu Department of Safety, Health and Environmental Engineering, Hung Kuang University 1

Outline Introduction Objectives Experimental Method Results and Discussion Conclusions Acknowledgements 2

Introduction 3

Fire Tetrahedron 4

Flame retardant mechanism Gas phase Condensed phase Heat Oxidation site Gas phase Condensed phase Polymer Materials 5

Flame retardants • Halogenated Flame Retardants： ex：Cl、Br… (PBB、PBDE、SCCP) PBDE Dioxin • Non-Halogenated Flame Retardants： ex： N、 P 、Si 、 IFR …. 6

Ro. HS and WEEE compliance Components and Materials 1. Lead 2. Mercury 3. Hexavalent chromium 4. Cadmium 5. PBB 6. PBDE Use of halogen flame retardant 7

Schematic illustration of expandable graphite preparation NG 8

Intumescent Flame Retardant (IFR) C + 2 H 2 SO 4 → CO 2 + 2 H 2 O + 2 SO 2 Carbon Foam Carbon source Blowing agent Acid HDPE/EG precursor 9

Polymerization of HDPE Monomer ： Ethylene (C 2 H 4) Ethylene structure . . . ＋ ＋ ＋ . . . Ethylene High Density Polyethylene 10

Objectives 11

Objectives • In this study, the H 2 O 2 -hydrothermal method was used to prepare EG and study its flame retardant performance of corresponding composites. 12

Experimental Method 13

Schematic illustration of Autoclave Airtight container Pressure Heat source ＊＊ o. C 14

The Flow Chart of Experiment 15

Results and Discussion 16

FT-IR spectra Fig. 2 FT-IR spectra of (a) NG (b) UEG (c) H 2 O 2 -EG. 17

XRD spectra (100 K) (140 K) (180 K) (500 K) (14 K) (e) (d) (c) (b) (a) Fig. 3 XRD patterns of (a) NG (b) CEG (c) UEG (d)H 2 O 2 -EG(e)H 2 O 2 -EGD. 18

SEM(1) (a) (b) Fig. 5 SEM micrographs of (a) NG(× 10 k) (b) H 2 O 2 -EG(× 10 k). 19

SEM(2) (a) (b) Fig. 6 SEM micrographs of (a) expanded graphite(× 0. 5 k) (b) expanded graphite (× 1 k). 20

Standard of LOI Level LOI Flammability ＜ 22 Self-extinguishing 22~25 Fireproof ≧ 26 21

Standard of UL-94 Standard Fire continued burning after the time away Dripping V-2 ＜ 30 S YES V-1 ＜ 30 S NO V-0 ＜ 10 S NO 22

LOI ＆ UL-94 testing results Table. 2 The LOI testing results of flame retarded HDPE composites. NG CEG UEG H 2 O 2 -EG Content LOI UL-94 rating LOI UL-94 rating 30% 24 fail 26 fail 27 fail 30 V-1 40% 24 fail 26 fail 29 fail 31 V-1 34 V-0 23

CONE 24

Heat release rate (HRR) Fig. 7 The Heat release rate (HRR) curves of the HDPE composites 25 by Cone calorimeter measurement.

Cone calorimetry data for HDPE 2 composites at 35 k. W/m Sample Tig (s) FO (s) PHRR TPHRR FGRI CY (k. W/m 2) (s) (k. W/m 2 s) (wt%) Pure HDPE 78 800 411 182 2. 26 20. 7 NG 30% 170 727 461 257 1. 79 29. 2 CEG 30% 62 667 406 137 2. 96 31. 0 UEG 30% 58 751 225 136 1. 65 32. 3 H 2 O 2 -EG 30% 57 770 198 132 1. 50 40. 1 26

Conclusions 27

Conclusions • EG is one kind of efficient halogen-free flame retardant for polymers. • The result showed the HDPE/EG composite possess excellent flame retardant property. 28

Acknowledgement • Kuang-Chung Tsai • Department of Safety, Health and Environmental Engineering • National Kaohsiung First University • Chia-Hsum Chen , Hsu-Chiang Kuan and Chen-Feng Kuan • Department of Material Science and Engineering • Far East University 29

Thanks for your attention 30