Poly(ε‐caprolactone)‐based additives: Plasticization efficacy and migration resistance

Abstract

A family of poly(caprolactone) (PCL)-based oligomeric additives was evaluated as plasticizers for poly(vinyl chloride) (PVC). We found that the entire family of additives, which consist of a PCL core, diester linker, and alkyl chain cap, were effective plasticizers that improve migration resistance. The elongation at break and tensile strength of the blends made with the PCL-based additives were comparable to blends prepared with diisononyl phthalate (DINP), a plasticizer typically used industrially, and diheptyl succinate (DHPS), an alternative biodegradable plasticizer. Increasing concentration was found to decrease glass transition temperature (T g ) and increase elongation at break, confirming their role as functional plasticizers. We found that all of the PCL-based plasticizers exhibited significantly reduced leaching into hexanes compared to DINP and DHPS. The PCL-based plasticizers with shorter carbon chain lengths reduced leaching more than those with longer carbon chain lengths.

Bio‐based glycerol plasticizers for flexible poly(vinyl chloride) blends

“…The opposite relationship was observed using hexanes, as the longer chained compounds showed the highest percentage of plasticizer loss; that is, DOTP, GS‐C6, GS‐C7, and GS‐EH at 55%, 40%, 42%, and 38% loss, respectively. A similar relationship was observed in a series of alkyl‐capped PCL star‐shaped plasticizers in which the compounds functionalized with longer aliphatic chains displayed higher levels of migration into hexanes 40 . Despite the fact that DOTP and GS‐EH are functionalized with the same 2‐ethylhexyl chain, the branched structure of GS‐EH (which emanates from the glycerol core) allows it to remain further embedded in the PVC matrix and resist migration from the blend when exposed to nonpolar media 33 …”

“…Among the glycerol analogs, there was a noticeable effect of the alkyl chain length on elongation at break (GS-iP and GS-C3 significantly different than GS-C4, GS-C6, GS-C7, and GS-EH, p < 0.001). It has previously been shown that poly(ε-caprolactone) (PCL) star shaped and linear dibenzoate alternative plasticizers demonstrated elongation at break values between 85% and 115% at 40 phr plasticizer loadings, 39,40 while linear succinate and fumarate based plasticizers obtained elongation at break values of up to 90% at 40 phr loadings. 41 Therefore, the obtained results for the glycerolsuccinate plasticizers are comparable to previous reports of alternative plasticizers.…”

“…A similar relationship was observed in a series of alkyl-capped PCL star-shaped plasticizers in which the compounds functionalized with longer aliphatic chains displayed higher levels of migration into hexanes. 40 Despite the fact that DOTP and GS-EH are functionalized with the same 2-ethylhexyl chain, the branched structure of GS-EH (which emanates from the glycerol core) allows it to remain further embedded in the PVC matrix and resist migration from the blend when exposed to nonpolar media.…”

Effects of modified tributyl citrate as a novel environmentally friendly plasticizer on the mechanical property and migration stability of soft polyvinyl chloride

“…[ 33 ] It is found that the volatility, extraction, and exudation test processes depend on the compatibility of the plasticizer with PVC, the polarity and structure of the plasticizer, temperature, media and other conditions. [ 39,40 ] Generally, the most important factor is the structure and compatibility of the plasticizer with PVC.…”

Assessments of classical dry-blending/moulding and solution casting PVC plasticization effectiveness – a comparative study

“…These two phenomena can occur simultaneously or separately 49 . When using n-hexane in migration studies, the extraction of plasticizer dominates, so the sample weight decreases 50,51 . As summarized in Table 1, the leaching of plasticizer from DEHP (also known in literature as DOP) plasticized specimens has been investigated in the temperature range from 23 o C to 50 o C, for the time from 2 h up to 168 h, for the plasticizer content from 30 to 100 phr, and for the specimen of thickness between 0.1 mm and 0.5 mm.…”