A series of amphiphilic hyperbranched polymers (AHP-s, the "s" refers to the algebra of AHP) were synthesized by the reaction between hydroxyl-terminated hyperbranched polymers (HBP-s, the "s" refers to the algebra of HBP) and palmitoyl chloride. FTIR, NMR and GPC were used to determine the structure of AHP-s, the results showed that AHP-s exhibits core-shell structure. The thermal properties of polymers were investigated by DSC and TGA. It was found that AHP-2, AHP-3 and AHP-4 display higher thermal stability than AHP-1 (AHP-1, AHP-2, AHP-3 and AHP-4 represent the first, second, third and fourth generation AHP, respectively). Furthermore, the self-assembly performance of AHP-s in THF solvent was investigated by TEM and SEM. Finally, the encapsulation capacity of the AHP-s for methyl orange (MO) was explored at different concentrations of AHP-s and pH conditions. It was found that AHP-s is capable of accommodating hydrophilic guest MO. Moreover, the higher generation of AHP-s, the stronger encapsulation capacity obtained. And the encapsulation capacity closely associated with the pH of encapsulation system.
In order to improve the adhesion and water resistance
of waterborne
polyurethane (WPU) adhesive, a kind of amino-terminated hyperbranched
organosilicon (HPSi-NH2) was first synthesized by using
trimethylchlorosilane, diethoxydimethylsilane, and γ-aminopropyltriethoxysilane
(KH550) as raw materials. Then, HPSi-NH2, as the cross-linking
agent, was used to modify the polyurethane prepolymer to obtain HPSi-NH2-modified WPU (HSiPU). The single-factor experiment results
showed that when the amount of HPSi-NH2 was 2.0 wt %, the
adhesion properties of HSiPU-2 were the best. Compared with the HSiPU-0
film, the water absorption rate of the HSiPU-2 film decreased by 10.9%,
the water contact angle increased by 26.3°, the tensile strength
increased by 10.1 MPa, and the elongation at break increased from
630.7 to 813.0%. HSiPU adhesive was used in the bonding of the goat
leather substrate, and the results showed that the peel strength of
leather bonded by HSiPU-2 was increased from 1.38 to 3.15 N/mm, and
the maximum peel force was increased from 1.67 to 5.51 N/mm, which
indicated that the bond strength of HSiPU adhesive with different
contents of HPSi-NH2 can be used for bonding substrates
with different cohesion strengths.
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