Allen G Pittman

Reactive Polymer Finishes for Wool. III. Phase Boundary Cross-Linking of Polyethylene Derivatives

Textile finishing by means of phase-boundary ..limited cross-linking (PBLC) of reactive polymers ( 13 and the general scope and utility of the method 111,. 7} liave been reported. The present paper explores in ~l1ore detail the utility of reactive polyethylene derivatives in phase-boundary limited cross<-’linking systems. The study also ittcltules extensive characterization of the textile properties of treated wool and characterization of the polymer wool etitity. . ’

Fabric Oil Repellency as Related to the Critical Surface Tension and Stiffness of Coating Material

Although a low critical surface tension for wetting ( 15 dynes/cm or less) is necessary for oil repellency, examples of fluoropolymers with low critical surface tensions are cited that are ineffective for making wool textiles oil repellent. In contrast to effective polymers, these have relatively high glass transition temperatures (ahove 25°C) and are therefore more brittle. Scanning electron microscopy of fabrics coated with such ineffective materials supports the idea that such coatings are flawed, fragile, and poorly adherent.

A New Class of Fluoroalkyl Acrylate Oil-Water Repellents Based on Fluorinated Ketones

gradient leads to condensation in the most effective insulating region of the fabric and a thermal resistance lower than predicted is observed. This finding is consistent with the usual practice of placing napped or pile fabrics with the fuzzy face towards the body. 5. On an absolute basis, losses in thermal resistance due to contained moisture are large compared to those due to differences in fiber arrangenient [3] but comparable to those due to changes in fabric thickness over the whote practical pressure range.

Grafting of Poly(1,1-Dihydroperfluoroalkyl Acrylates) on Wool

Copolymers of 1,1-dihydroperfluorooctyl acrylate/methacryloyl chloride acted as multipurpose finishing agents for wool. They provided oil and water repellency; resistance to felting shrinkage; and resistance to acid, alkali, and oxidizing media. The hand and flexural rigidity were altered slightly, whereas wrinkle recovery, fabric break, tear strength, and abrasion resistance were not significantly changed. Grafting of the copolymers on wool is presumed to be due mainly to a reaction between copolymer-acid chloride groups with hydroxy and amino groups in keratin. Aside from rendering the polymer insoluble to dry cleaning solvents, grafting permitted the use of smaller amounts of resin for shrinkage protection than was required with nongrafted polymer. The washfastness of the oleophobic-hydrophobic finish was essentially the same in a comparison of a grafted copolymer fluoroalkyl acrylate and a nongrafted homopolymer fluoroalkyl acrylate. No significant differences were noted in the washfastness or fastness to dry cleaning of the oleophobic-hydrophobic finish imparted by a commercial fluorinated acrylic resin (FC 208) when the resin was applied on untreated wool, on shrink resistant wool fabrics, or in conjunction with an interfacial polymerization shrinkproofing technique.

Reactive Polymer Finishes for Wool Part IV: Phase Boundary Limited Cross-Linking of Reactive Polyesters and Polyethers to Yield Polyurethanes

A study of the application of several reactive urethane elastomer finishes [based on polyesters or polyethers] to wool is reported. The polymer is applied to the wool in an organic solvent and cross-linked by a diamine applied separately in aqueous solution. Several textile properties of the treated wool are reported. The treated wool has good resistance to felting shrinkage during machine laundering with little or no alteration in the desirable physical and textile properties of the wool.

Textile Finishing: Phase Boundary Limited Cross-Linking of Reactive Polymers

()))<&dquo;) 2 min : olï t&dquo;)’ min ( ) 11 i ( I I’ min : <’)))<’r!0)))i)) On to) ](I 111 ill: <>li I<>r 11) iiiiii A steady state appeared to be reached by the end of each &dquo;off&dquo; period, and thetma1<)eformationBBassuhstantiatty unchanged even after a further 11)-tttin boding. The deformations ;vt the ends o) successive on otYcyctes were therefore taken as &dquo;permanent viscous deiormatiolb; the:-.e 1)1()tte(i ill Figure 2. The dl’Ïol&dquo;matio11 inlTea:-.e~ curBi)inear)y witlt time. hut if the force(1(.fol-lll;ttl4)11 curve of &dquo;Figure 1 i.. u:-.ed to c’)!ivert deformation liito it is found that the elective vi~co--itB in each ra~e IN r011~tant throug&dquo;hout tlte tua. Xative nhers are highly . cmntltrr:·~·ci hy this treatment. and tttirr m·rml~irul examination after tea ~hoBB’~ the presence of &dquo;t1at-<&dquo; on the r~natln-e..e,l surfaces. Siiigl« l’xpl’ril11ent... il1u:-.trated hy 1-’Igiii-c 2. indicatl’el that tlte illt1ul’nl’l’ oi ;lcid and oi iormaldehyde pretreatn1l’nt i. to reduce tltr deformation, i.e..to increase the lateral viscosity at 11111&dquo; (’. Both oi tlll’’’l’ t.reatn1l’nb reduce tIlt’ ettectiBeness of p)eatinjn operations on woo) fabrics. although 11Ime dramatically than BBould he expected on the hasis of the present r~·.ult·. The Iitei-;tl B’i:-.co..ity oi Ilatin> ill w;ttcr wa· found to increase rapidly as the temperature decreased. In separate experiments witlt different hatches of 111)(.’1&dquo; it BBas found that the viscosity at 71)° C Bvas over twenty tinBe:, the It lOW {-. Thi~ i~ again in !,eiiii(iii;iiitit.,ItlB,e agreement with I;il>11<~-j>le;itiiig tests. It may he concluded that lateral compression is a possihte mechanism operating in setting processes in woo) fabrics. ,

The effects of ethylene glycol on wool fibers.

We have previously shown that ethylene glycol can be a useful solvent for certain continuous processes in wool textile finishing. A brief treatment in hot ethylene glycol can (1) impart considerable stretch properties to woven wool fabric when treated in a slack condition (Pittman and Wasley, 1974; Pittman and Wasley, 1975), (2) produce permanent set, i.e. creases or crimp, to wool held in a constrained configuration during treatment (Pittman et al., 1975) and (3) produce rapid and thorough dyeing when used as a dyebath medium (Pittman et al., 1976).