Synthesis Of New Anionic Polysiloxanes And Their Electrostatic Assembly On Fibers

In recent years, the continuous development of the supramolecularassembly provides an effective way of preparing multifunctional textilefinishing agent with diversified styles and features. Using theelectrostatic interaction or H-bond as driving forces, We can assembleanionic and cationic polysiloxanes to form siloxane supramolecular.After dipping in the supramolecular system, the fiber substrate is loadedby a layer of polysiloxane supramoleculars, so the softeness,wettability, antistatic behavior and comprehensive hand-feeling of thefinished textiles can be improved for the synergistic interaction ofdifferent functional groups. In this way, we improved theproduct-addition value of the textile as well as meet the increasedrequirments of production and life.Therefore, we synthesied a series of new anionic polysiloxanesco-modified by carboxyl group and some other fuctional groups andassembled them with cationic amino functional polysiloxanes. Afterthat we fixed the supramolecular on cotton and wool substrates andcharacterized the film morphology and chemical composition of thefilm by SEM, ATR and XPS. Enlightened by the thought of electrostaticassenmbly, we emulsified the anionic and cationic polysiloxanes intomicro-emulsification, and mixed them up to obtain electrostaticcomposite emulsion with reverse charges which was then used as textilefinishing agent. The softness, wettability, hand-felling of the finishedcotton or wool textiles was investigated in this paper. （1） A star-shaped carboxyl/polyether co-modifiedtetramethylcyclotetrasiloxane （CPECS） is firstly synthesized by theesterification reaction between the maleic anhydride and polyethertetramethylcyclotetrasiloxane （PECS） which was prepared by thehydrosilylation between tetramethylcyclotetrasiloxane （D₄H） and anallyl polyether. The chemical structure is characterized by IR,1H-NMR.Using CPECS and ASO-1as architecture units, the supramolecularCPECS/ASO-1was constructed in ethyl acetate and then fixed on thefiber substrates. The SEM photography， ATR and XPS spectra of thefibers treated by CPECS/ASO-1indicate that CPECS/ASO-1system canform relatively smooth films on the cotton and wool substrates.According to electrastatic assembly theory, we mixed the CPECSwater solutions with negative charges and the ASO-1emulsion withpositive charges to obtain electrastatic composite emulsionCPECS-s/AS-e, and the performance of CPECS-s/AS-e as textilefinishing agent was studied. The result indicated that when theproportion of CPECS-s increased, the softness of the cotton fabrictreated by CPECS-s/AS-e was decreased, while the whiteness and thewater absorption ability improved. The performance of the treatedcotton fabric is best when the weight ratio of the CPECS-s to AS-e is1:2. When used as smoothing agent, the CPECS-s/AS-e can improve thesoftness, smoothness, and antistatic properties of the wool textilesignificantly.We also deposited AS-e and CPECS-s on cotton substratealternately to form layer-by-layer films. Along with the increasing ofthe polysiloxane layer, the softness of the cotton fabric increased whilethe whiteness decreased. The wettability of the fabric related to theoutermost polysiloxane layer. The polysiloxane films shed seriouslywhen the layer deposited over four.（2） Using1,3-bis（3-aminopropyl）tetramethyldisiloxane as theblocking agent of the ring-opening polymerization of D4, a novelamino-terminated polysiloxane （ATPS） was synthesized. Then byreacting with maleic anhydride, ATPS can be turned into carboxyl-terminated polysiloxane （CTPS）.A supramolecular was constructed by mixing the ATPS ethylacetate solution and CTPS ethyl acetate solution up. By immersing thefiber substrate in the ATPS/CTPS, a smooth film was obtained on thecotton and wool fibers which can fill in the gully of the cotton fiber andcover the scale-like wool fibers.Emulsifing the ATPS and CTPS, we got stable micro-emulsion andthen mixed the emulsions with reverse charges to prepare electrastaticcomposite emulsion ATPS-e/CTPS-e which was used in textilefinishing. The performance properties of the ATPS-e/CTPS-e wereinvestigated by flexibility tester, leucometer and other instruments. Theresults indicated that cotton fabric treated by ATPS/CTPS has bettersoftness, elasticity and smoothness especially when mixing the ATPS-eand CTPS-e equally. When used as wool smoothing agent,ATPS-e/CTPS-e supramolecular can make the wool textile haveexcellent softness, antistatic properties and a pleasant oily feeling.（3） A carboxyl modified polyether/amino polysiloxane （CPEAS）was synthesized by the reaction of maleic anhydride andpolyether/amino polysiloxane. Chemical structure was verified by IRand¹H-NMR.We assembled the CPEAS and APES in ethyl acetate toconstructure supramolecular CPEAS/APES, and then fixed theCPEAS/APES on the cotton fiber substrate, whose morphology andchemical composition were charactered by SEM, ATR and XPS.A stable CPEAS emulsion was prepared and used to constructelectrastatic composite emulsion with amino/polyether co-modifiedpolysiloxane （APES） emulsion. The performance properties of thecomposite emulsion CPEAS-e/APES-e were evaluated throughinvestigation of the softness, wettability and hand-feeling of the treatedcotton fabric. The influence factors affecting the performance, such asemulsifier proportion, pH, weight ratio of CPEAS-e to APES-e werealso discussed. The results indicates that, when the weight ratio ofCPEAS emulsion containing20-30%emulsifier and without alkali and the weight ratio of CPEAS-e to APES-e is2:1, the CPEAS-e/APES-eturned to be an excellent hydrophilic softening agent.