TY - JOUR
T1 - Synthesis and Curing of Hyperbranched Poly(triazole)s with Click Polymerization for Improved Adhesion Strength
AU - Tang, Youhong
AU - Jim, Cathy
AU - Liu, Yang
AU - Ye, Lin
AU - Qin, A
AU - Lam, W
AU - Zhao, Chengbi
AU - Tang, Ben
PY - 2010/2/24
Y1 - 2010/2/24
N2 - We successfully synthesized hyperbranched poly(triazole)s by in situ click polymerization of diazides 1 and triyne 2 monomers on different metal surfaces (copper, iron, and aluminum) and characterized their adhesive properties. Optimizations were performed to obtain high adhesive strength at different temperatures by analyzing the effects of curing kinetics, annealing temperature and time, catalyst, monomer ratio, surface conditions, alkyl chain length of diazides 1, etc. The adhesive bonding strength with metal substrate is 2 orders of magnitude higher than similar hyperbranched poly(triazole)s made by click polymerization and clearly higher than some commercial adhesives at elevated temperatures. With the same conditions, adhesives prepared on aluminum and iron substrates have higher adhesive strength than those prepared on copper substrate, and an excess of triyne 2 monomer in synthesis has greater adhesive strength than an excess of diazide 1 monomer. Tof-SIMS experiment was employed to understand these phenomena, and the existence of an interphase between the polymer and metal surface was found to be critical for adhesive bonding with thicker interphase (excess of triyne 2 monomer) and the higher binding energy between polymer atoms and substrate atoms (e.g., aluminum substrate) generating the higher bonding strength. In addition, the light-emitting property of synthesized polymers under UV irradiation can be used to check the failure mode of adhesive bonding.
AB - We successfully synthesized hyperbranched poly(triazole)s by in situ click polymerization of diazides 1 and triyne 2 monomers on different metal surfaces (copper, iron, and aluminum) and characterized their adhesive properties. Optimizations were performed to obtain high adhesive strength at different temperatures by analyzing the effects of curing kinetics, annealing temperature and time, catalyst, monomer ratio, surface conditions, alkyl chain length of diazides 1, etc. The adhesive bonding strength with metal substrate is 2 orders of magnitude higher than similar hyperbranched poly(triazole)s made by click polymerization and clearly higher than some commercial adhesives at elevated temperatures. With the same conditions, adhesives prepared on aluminum and iron substrates have higher adhesive strength than those prepared on copper substrate, and an excess of triyne 2 monomer in synthesis has greater adhesive strength than an excess of diazide 1 monomer. Tof-SIMS experiment was employed to understand these phenomena, and the existence of an interphase between the polymer and metal surface was found to be critical for adhesive bonding with thicker interphase (excess of triyne 2 monomer) and the higher binding energy between polymer atoms and substrate atoms (e.g., aluminum substrate) generating the higher bonding strength. In addition, the light-emitting property of synthesized polymers under UV irradiation can be used to check the failure mode of adhesive bonding.
KW - Adhesion strength
KW - Click polymerization
KW - High-temperature adhesive
KW - Hyperbranched poly(triazole)s
KW - Light emission
UR - http://www.scopus.com/inward/record.url?scp=84862833599&partnerID=8YFLogxK
U2 - 10.1021/am9008727
DO - 10.1021/am9008727
M3 - Article
SN - 1944-8244
VL - 2
SP - 566
EP - 574
JO - ACS Applied Materials & Interfaces
JF - ACS Applied Materials & Interfaces
IS - 2
ER -