TY - JOUR
T1 - Characterization and Chain Structure of PEG/PBT Copolymer with the Constant Mass Ratio of Soft to Hard Segment
AU - Zhang, Yong
AU - Ye, Ling
AU - Feng, Zeng Guo
AU - Zhang, Ai Ying
AU - Tian, Xiao Juan
AU - Xu, Rui Xing
PY - 2002/10
Y1 - 2002/10
N2 - A series of polyether ester thermoplastic elastomers based on polyethylene glycol(PEG) and poly (butylene terephthalate) (PBT) are synthesized and characterized by means of NMR, FTIR and DSC and mechanical testing. The influence of the constant mass ratio (70/30) of soft to hard segment on the copolymer's thermal and mechanical properties is investigated. It is found that, firstly, the length of hard segments is increased with increasing PEG molecular weight from 400 to 4 000(M̄n); secondly, four domains corresponding to the amorphous and the crystal phase of soft and hard segments coexist in some compositions; thirdly, the glass transition temperature(Tg) of the soft segment is decreased, meanwhile its molten point(Tm) and the degree of crystal(wc) are increased with the increase of its molecular weight; finally, the inherent viscosity changes from 1.23 to 1.64 dL/g with ascending PEG molecular weight and shows a slight depression after the molten moulding which can be ascribed to a thermooxidative degradation. All copolymers are distinguished by the high elastic deformation in the stress-strain curves. With the increase of PEG molecular weight, the elongation at break εb, the tensile strength σb and the yield stress σy are all improved, while the elastic modulus E changes slightly around 9 MPa.
AB - A series of polyether ester thermoplastic elastomers based on polyethylene glycol(PEG) and poly (butylene terephthalate) (PBT) are synthesized and characterized by means of NMR, FTIR and DSC and mechanical testing. The influence of the constant mass ratio (70/30) of soft to hard segment on the copolymer's thermal and mechanical properties is investigated. It is found that, firstly, the length of hard segments is increased with increasing PEG molecular weight from 400 to 4 000(M̄n); secondly, four domains corresponding to the amorphous and the crystal phase of soft and hard segments coexist in some compositions; thirdly, the glass transition temperature(Tg) of the soft segment is decreased, meanwhile its molten point(Tm) and the degree of crystal(wc) are increased with the increase of its molecular weight; finally, the inherent viscosity changes from 1.23 to 1.64 dL/g with ascending PEG molecular weight and shows a slight depression after the molten moulding which can be ascribed to a thermooxidative degradation. All copolymers are distinguished by the high elastic deformation in the stress-strain curves. With the increase of PEG molecular weight, the elongation at break εb, the tensile strength σb and the yield stress σy are all improved, while the elastic modulus E changes slightly around 9 MPa.
KW - Mechanical properties
KW - PEG/PBT copolymer
KW - Thermoplastic elastomer
UR - http://www.scopus.com/inward/record.url?scp=0346008216&partnerID=8YFLogxK
M3 - Article
AN - SCOPUS:0346008216
SN - 0251-0790
VL - 23
SP - 1986
EP - 1987
JO - Kao Teng Hsueh Hsiao Hua Heush Hsueh Pao/ Chemical Journal of Chinese Universities
JF - Kao Teng Hsueh Hsiao Hua Heush Hsueh Pao/ Chemical Journal of Chinese Universities
IS - 10
ER -