Fluorocarbon Elastomer Processing Aid in Film Extrusion of Linear Low Density Polyethylenes

Rudin, Alfred; Worm, Allan T.; Blacklock, John E.

doi:10.1177/875608798500100303

Cited by 15 publications

(8 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In order to overcome extrudate distortions and to render the processes economically feasible, polymer processing aids (PPAs) are frequently used (Rudin et al 1986;Priester et al 1993;Rosenbaum et al 1995;Hatzikiriakos et al 1995;Amos et al 2001;Achilleos et al 2002). PPAs can eliminate melt fracture phenomena such as sharkskin or postpone them to higher shear (flow) rates.…”

Section: Processing Aidsmentioning

confidence: 99%

“…The end result is an increase of the productivity as well as an energy cost reduction, while high product quality is maintained. The additives mostly used are fluoropolymers (Rudin et al 1986;Priester et al 1993;Amos et al 2001) especially designed for polyolefin extrusion processes. Amos et al (2001) and Achilleos et al (2002) have reviewed the formulation, applications and performance of various processing aids.…”

Section: Processing Aidsmentioning

confidence: 99%

See 1 more Smart Citation

Wall slip and melt fracture of poly(lactides)

et al. 2011

View full text Add to dashboard Cite

The wall slip and melt fracture behaviour of several commercial polylactides (PLAs) as well as their rheological properties under shear and extensional have been investigated. The PLAs have had weight-average molecular weights in the range of 10 4 -10 5 g/mol and studied in the temperature range of 160-200 • C. The solution properties and linear viscoelastic behaviour of melts indicate linear microstructure behaviour. PLAs with molecular weights greater than a certain value were found to slip, with the slip velocity to increase with decrease of molecular weight. The capillary data were found to agree well with linear viscoelastic envelope once correction for slip effects was applied. The onset of melt fracture for the high molecular weight PLAs was found to occur at about 0.2 to 0.3 MPa, depending on the geometrical characteristics of the dies and independent of temperature. Addition of 0.5 wt.% of a polycaprolactone (PCL) into the PLA that exhibits melt fracture was found to be effective in eliminating and delaying the onset of melt fracture to higher shear rates. This is due to significant interfacial slip that occurs in the presence of PCL.

show abstract

Section: Processing Aidsmentioning

confidence: 99%

Section: Processing Aidsmentioning

confidence: 99%

Wall slip and melt fracture of poly(lactides)

et al. 2011

View full text Add to dashboard Cite

show abstract

“…One is based on the stick‐slip at the die wall,5–11 and the other is based on the periodic growth and relaxation of tensile stress at the extrudate surface at the die exit 12–21. The following methods to suppress the sharkskin are known: (1) increasing the resin temperature;12, 13, 22, 23 (2) decreasing only the die part temperature;13, 24, 25 (3) choosing the die material;5, 11 (4) fluorinating the die wall,20 coating the die wall with Teflon10 and fluorocarbon elastomer,19 and coating the die exit part with soap water;21 (5) broadening the molecular weight distribution of the resin;9, 13, 23, 26, 27 (6) decreasing the molecular weight of the resin;23, 26 and (7) adding to the resin external lubricants such as fluorocarbon elastomer,5, 28–30 silicone,29, 31 hyperbranched polymer,32 and boron nitride33, 34 to promote the slip of the resin at the die wall. For the method of adding the resin external lubricants such as fluorocarbon elastomer, there are drawbacks that an incubation time of up to 1 h is needed until the effect appears after the start of extrusion and that a time to exchange the resin in the extruder after extrusion is needed 5, 30.…”

Section: Introductionmentioning

confidence: 99%

Melt fracture behavior of polypropylene‐type resins with narrow molecular weight distribution. II. Suppression of sharkskin by addition of adhesive resins

Fujiyama

Inata

2002

J of Applied Polymer Sci

View full text Add to dashboard Cite

Standing on a hypothesis that the sharkskin of a polymer with a narrow molecular weight distribution at extrusion processing originates from a stick-slip of the polymer at the die wall, the suppression of the sharkskin was tried by means of suppressing the slip by the addition of adhesives. To polypropylene (PP)-type resins with narrow molecular weight distributions such as a PP-type thermoplastic elastomer, PER and a controlled rheology PP were added small amounts of adhesives such as maleated PP, maleated PER, reactive polyolefin oligomers, ethylene/ethylacrylate/ maleic anhydride (MAH) copolymer, ethylene/vinyl acetate copolymer, and styrene/ MAH copolymer, and their melt fracture behaviors at capillary extrusion were observed. It was found that the sharkskin of the PP-type resins with narrow molecular weight distributions was suppressed by the addition of the adhesive resins with good adhesion to metal. The suppressive effect of the sharkskin was generally the more remarkable by the higher loading of the adhesives with the higher MAH content. This is the direction of increasing adhesion. From this fact, it was assumed that the sharkskin of the PP-type resins with narrow molecular weight distribution does not originate from a periodic growth and relaxation of tensile stress at the extrudate surface but from a stick-slip at the die wall. Based on this mechanism, it may be said that the sharkskin can be suppressed by both ways of directions of promoting and suppressing the slip at the die wall. The former way is the previously known method, and the latter way is the method proposed in the present study.

show abstract

“…HE USE OF fluorocarbon based polymer processing additives (PPAs) for the elimination of melt fracture in linear polyethylenes (1) has become well established in the film industry. Likewise, the relationship of this additive with other common polyolefin additives has been intensively researched and documented [2][3][4][5][6].…”

Section: Introductionmentioning

confidence: 99%

The Influence of Polymer Processing Additives on the Surface, Mechanical, and Optical Properties of LLDPE Blown Film

Blong

Klein

Pocius

et al. 1994

Journal of Plastic Film & Sheeting

View full text Add to dashboard Cite

Linear Low Density Polyethylene (LLDPE) film was blown from both wide and narrow die gaps, with and without two commercial polymer processing additives. Wide die-gap extrusion was used to determine how the physical presence of either processing additive affected various mechanical and optical properties of the resultant films. Narrow die-gap extrusion demonstrated how polymer processing additives can be utilized to improve extrusion parameters and permit production of films with improved properties. Surfaces of all the films were analyzed prior to and after corona treating; there were no effects of either additive on contact angle or surface energy. Monitoring over a one year period showed no evidence of either processing additive nor any differences in element composition on the surfaces of the films.

show abstract

Fluorocarbon Elastomer Processing Aid in Film Extrusion of Linear Low Density Polyethylenes

Cited by 15 publications

References 11 publications

Wall slip and melt fracture of poly(lactides)

Wall slip and melt fracture of poly(lactides)

Melt fracture behavior of polypropylene‐type resins with narrow molecular weight distribution. II. Suppression of sharkskin by addition of adhesive resins

The Influence of Polymer Processing Additives on the Surface, Mechanical, and Optical Properties of LLDPE Blown Film

Contact Info

Product

Resources

About