Today, there is a steadily increasing demand for the application of surfactants as debonding agents in tissue manufacturing. The work presented herein focused on evaluating the debonding ability of cationic alkoxylated amine surfactant on unrefined and refined fibers. The results showed that, as the dosage of the surfactant was increased to 10 mg/g on unrefined pulps, the adsorption of the surfactant on the fibers increased to 5 mg/g, and the tensile and burst indices of the papers made of the modified fibers decreased by as much as 12.6% and 14.9%, respectively. Also, the roughness, strain, and moisture content of the papers were enhanced, whereas the apparent density was reduced. Furthermore, the tear index of the papers increased upon the application of surfactant (10 mg/g) at the expense of reductions in tensile and burst indices, as well as the apparent density at any pressure applied in wet pressing. Also, as the pressure was increased, the surfactant impacted the fiber bonding more significantly. On the other hand, the application of surfactant (10 mg/g) somewhat increased the light scattering coefficient of the papers, regardless of the refining load. Furthermore, the adsorption of the surfactant on refined fibers increased with increasing refining load. However, the influence of the surfactant on the tear, tensile, and burst indices and the apparent density was impaired with increasing refining load. Also, the zero-span tensile index and brightness of the papers varied negligibly upon surfactant application.

Debonding agents are applied in the paper industry for various purposes, for example, to increase the softness of tissue paper. In this work, the debonding capacities of three cationic aliphatic ammonium surfactants and one alkoxylated amine surfactant on kraft fibers were determined. The results showed that the adsorption of the alkoxylated amine surfactant (AAS) was higher than that of others on the fibers, but a cationic cetyltrimethyl ammonium surfactant (cetyltrimethyl ammonium bromide, CAB) was the most effective debonding agent, probably because of its relatively long hydrophobic chain. By applying CAB at levels of up to 20 mg/g, the tensile and burst indices were reduced by 37% and 41%, respectively. By applying AAS at levels of up to 20 mg/g, the tensile and burst indices of the networks were reduced by 18.6%, and 14.2%, respectively. The tear index of the fiber networks negligibly changed upon application of AAS, but increased by 19% upon application of CAB. The strain of the fiber networks prior to rupturing increased upon application of AAS, whereas it decreased upon application of CAB, which implies that the surfactants have different debonding mechanisms. The debonding efficiency of CAB was independent of both the refining revolutions and basis weights of the fiber networks.