A new strategy for plasticizing and stabilization of PVC mixtures

Abstract

This study was undertaken to examine possible use of classic tetravalent tin‐based heat stabilizers for the preparation of a polymer plasticizer: poly(ε‐caprolactone) (PCL) and simultaneous stabilization of PVC in PVC/PCL mixtures. PCL was prepared from ε‐caprolactone (CL) by polymerization initiated by tin‐containing organic compounds and successfully used to simultaneously plasticize and stabilize PVC. Moreover, conditions under which the polymerization of CL took place directly in situ during PVC/CL mixture processing were found. The procedure yielded homogeneous plasticized PVC/PCL mixtures, which were stable and contained >90% of the original monomer content. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41066.

In situ formed poly(ε-caprolactone) as a novel non-toxic plasticizer of poly(vinyl chloride)

“…Details of NMR evaluation can be found in our previous publication. 15 As expected, the total concentration of plasticizer in the mixture increased with increasing CL 0 content, but the increase in polymerized CL was slower (Figure 4). After kneading and molding, approximately 90 -95% of the supplied CL 0 plasticizer remained in the mixture while the proportion of polymerized CL (PCL) in the plasticizer (detectable in NMR at 4.00 ppm) was about 70 -80% (Table 2, Figure 4).…”

“…The stabilizer used (dibutyltin maleate) is very efficient and several mechanisms are involved during the stabilization of PVC (formation of complex between PVC and Sn compound as indicated in Figure 1, HCl neutralization, Cl substitution, Diels-Alder reaction, etc. 15,18 However, during mixing of PVC and CL in an open system (two-roll mill), most of the CL flows out. Nevertheless, similar complications, although to a lesser extent, also exist when mixing classical low-molecular weight plasticizers, for example diisononyl adipate, 2,2,4-trimethyl-1,4-pentanediol diisobutyrate, but also di(2-ethylhexyl) phthalate and tris (2-ethylhexyl) trimellitate.…”

“…The loss of CL can be avoided by pre-polymerization it at processing temperature in a separated vessel. 15 Then, the resulting polymerizate (61% conversion, molar mass 3-4 kg.mol À1 ) can be added as a plasticizer and stabilizer to PVC and the mixture can be rolled. During the rolling process, the unreacted monomer is partially post-polymerized.…”

Principles of Thermal Degradation

“…292 Addition of montmorillonite further increases thermal stability of the blend. 293 Tin-containing compounds can be used as catalysts of caprolactone polymerization and then remaining catalyst acts as PVC thermal stabilizer. 293 Tin-containing compounds can be used as catalysts of caprolactone polymerization and then remaining catalyst acts as PVC thermal stabilizer.…”

Toughening PVC with Biocompatible PCL Softeners for Supreme Mechanical Properties, Morphology, Shape Memory Effects, and FFF Printability

“…In the past, heat stabilizers based on lead were more used, which have been replaced by calcium/zinc mixtures and organic compounds based on tetravalent tin due to environmental issues. [ 5 ] On the other hand, the environmental issue of the use of plasticizers has been pursued more seriously. In the past years, phthalates, especially diethyl hexyl phthalate (DEHF), were considered the first option for softening PVC due to their low cost and high compatibility.…”