Nghiên cứu tương tác PANi/EGCG trong quá trình Polyme hóa điện hóa. Phần 2

TAP CHI HOA HOC T. 51(6)700-703 THANG 12 NAM 2013

NGHIEN CU'U TU'ONG TAC PANi/EGCG

TRONG QUA TRJNH POLYME HOA DIEN HOA

2. TAG DONG COA EGCG BtU KHO\ MAO POLYME HOA ANi

Mai Thanh Nga'*, Mai Tuyen\ Le Xuan Que^

' Trudng Dgi hgc Suphgm Thdi Nguyen

'Vien Hoa hgc Cdng nghiep Viet Nam

^Vien Ky thudt nhiet doi. Viin Hdn ldm Khoa hgc vd Cdng nghe Viet Nam

Dan Tda soan 20-9-2012

Abstract

This paper presents the second part - the EGCG effects on the mitiation of ANi polymerization. It was found that

EGCG at concentration 1-3 g/1 generally increased the initiation of ANi polymerization at the first 10 CV cycles, but

after 10'"' CV cycle decreased the rate of the polymerization at the all concentration. EGCG affected the plymerization

according to an adsorption mechamsm. EGCG adsorbed on the active sites in the PANi chains on the elecUode surface

and thus prevented the ANi polymenzation process. But m general this adsorption did not affect the PANi oxidation

process.

Keywords: PANi, EGCG, electrochemical polymerization, cyclic voltammetry, Initiatton.

I. GIOI THIEU

Polyphenol (catechin) dugc chiet tach tir che

xanh, thudng dugc sii dung lam dd udng [1, 2]. Cd 5

chat chinh: (+)-catechin, (-)-epicatechin,

(-)-epigallocatechin, (-)-epicatechin gallat, va

(-)-epigallocatechin gallat (EGCG) (hinh I).

(-)-epic3lechm gallale [-)-epigallocatecnin gallale

Hinh T. Cac polyphenol chiet tach tir che xanh

Polyme hda cac catechm, tao thanh

polycatechin, dugc thuc hien vdi tac nhan oxi hda

trong mgt sd dung moi [3-5]. Polyme hda

polyphenol che xanh cdn dugc nghien cihi dinh

hudng ling dung y hgc [6-8].

Polyphenol che xanh noi chung va neng EGCG

deu cd hieu irng iic che an mdn vdi hieu suat lie che

cao [9-11], va dugc nghien ciru iing dung lam chat

lie che trong cac dung djch tay riia, lam sach be mat.

Tiep theo bai gidi thieu ky thuat xac djnh cac

thdng sd hda ly tir dudng cong phan cue CV [12],

bai bao nay trinh bay ket qua nghien ciru anh hudng

ciia EGCG den khai mao polyme hda anilin (ANi).

2. PHLTONG PHA P

De nghien cim anh hudng den qua trinh polyme

hda ANi, EGCG dugc pha che true tiep vao dung

djch tdng hgp, vdi ndng do 0-5 g/1. Hgp chat EGCG

dugc chiet tach tir la che xanh, dugc tinh che dat den

do tinh khia 98 %. Mdt so tinh chit cua EGCG thu

dugc:

Nhiet dp ndng chay: 215,4 °C

Mau sac: Trang

Do tinh khiat: 98 %

Trpng lugng phan tir: 458.

Bdng 1: Ki hieu mau va ndng dp EGCG (g/1)

Ki hieu

EGCG, g/1

MO

0

Ml

0,25

M2

0,50

M3

1,00

M4

2,00

M5

3,00

M6

5,00