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displayed higher melt viscosities with
increasing St/AA ratios and a more pesu-
doplastic type behavior than the control
LDPE, in particular in the low shear rate
range which is more sensitive to interchain
interactions. Similar effects have been
found for GMA-grafted polyolefins
[17]
and this could be mostly ascribed to polar
interactions between polar groups of AA in
the polymers chains. However, the marked
increase observed in the melt viscosity of
LDPE-
Rheological properties indicated that
LDPE-g-(AA-St) made at various feed
compositions displayed higher melt viscos-
ities with increasing St/AA ratios and more
pesudoplastic behavior than the control
LDPE samples, in particular in the low
shear rate range. This copolymer with high
reactivity and better flow properties could
be widely used as a compatibilizer for
LDPE and other polar polymers.
-(AA-St) could not be accounted
only by the effect of the grafting degree of
the LDPE and suggested the possible
occurrence of crosslinking reactions
between the grafted chains in the melt.
[18]
g
[1] J. H. Yang, Z. H. Yao, D. N. Shi,
J. Appl. Polym. Sci.
2001, 79, 535.
[2] Q. Shi, L. C. Zhu, C. L. Cai, Polymer 2006, 47, 1979.
[3] M. F. Lu, S. J. Zhang, D. S. Yu,
J. Appl. Polym. Sci.
2004, 93, 412.
[4] P. Mariano, C. Donatella, Macromol. Symp. 2004,
218, 173.
[5] Y. H. Wang, F. B. Chen, K. C. Wu,
Conclusions
J. Appl. Polym. Sci.
2004, 93, 100.
[6] F. Pazzagli, M. Pracella,
AA has been successfully grafted onto the
LDPE backbone in the presence of DCP.
LDPE-
Macromol. Symp. 2000,
149, 225.
[7] X. Y. Qiao, Y. Zhang, Y. X. Zhang,
J. Appl. Polym. Sci.
-(AA-St) with high grafting degree
of AA could be obtained when styrene was
added to the melt grafting system. When
the St/AA ratio was less than or equal to 1,
increasing the concentrations of St
improves the grafting degree of AA and
the optimum molar ratio was 1. The flow
properties of LDPE-
g
2004, 91, 2320.
[8] P. Ghosh, B. Chattopadhyay, A. K. Sen,
Polymer
1998,
, 193.
[9] H. L. Huang, Z. H. Yao, J. H. Yang,
39
J. Appl. Polym. Sci.
2001,
, 2538.
[10] Z. H. Yao, Y. Gao, J. H. Yin,
80
J. Appl. Polym. Sci. 2002,
86, 2626.
[11] M. Z. Liu, Z. M. Liu, S. L. Ding,
J. Appl. Polym. Sci.
-(AA-St) could be
adjusted by tailoring the St/AA ratio under
this condition. But the hydrophobic nature
of LDPE-g-(AA-St) was not consistent
with the grafting degree of AA when St
was used as a comonomer. When the St/AA
ratio was 0.1, the LDPE-g-(AA-St) pos-
sessed better hydrophilicity. Suitable DCP
and AA concentrations were about 0.2 wt%
and 5 wt%, respectively for comprehensive
properties of modified LDPE. The suitable
modification time was about five minutes.
g
2003, 90, 3299.
[12] M. W. Pan, L. C. Zhang, J. F. Yuan,
J. Appl. Polym.
Sci. 2005, 95, 419.
[13] Y. Li, X. M. Xie, B. H. Guo, Polymer 2001, 42, 3419.
[14] T. H. Kim, H. K. Kim, D. R. OH,
J. Appl. Polym. Sci.
2000, 77, 2968.
[15] S. J. Kim, B. S. Shin, J. L. Hong,
Polymer 2001, 42,
4073.
[16] H. L. Wang, H. R. Brown,
J. Polym. Sci. Pol. Chem.
2004, 42, 263.
[17] M. Pracella, D. Chionna, Macromol. Symp. 2003,
198, 161.
[18] B. Wong, W. E. Bake,
Polymer
1997, 38, 2781.
