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Impact modifiers.


Polybutene improves impact resistance of many thermoplastics, including crystal PS, high-impact PS, PP homopolymer, and elastomer-modified PP. Polybutenes are clear and stable viscous polymers with little or no odor plus resistance to thermal degradation. Available in a wide range of viscosities.

In PS, polybutenes can improve impact resistance and melt flow. When used in place of mineral oil, physical properties of PS are less affected and there is an improvement in the impact resistance.

In modified PP and in resin that has been modified with a thermoplastic elastomer (TPE), polybutenes are said to dramatically improve impact resistance, which suggests that polybutenes may be used to enhance impact strength and partially replace more expensive TPE.


Produces ground rubber from recycled car and truck tires. Granulite products come in a variety of particle sizes down to minus 40 mesh. They can be used as flexibilizers, anti-skid additives, extenders, and potentially as impact modifiers. Company plans to introduce pelletized masterbatches of ground rubber in a thermoplastic vehicle.


See DSM Copolymer, Inc.


Seven grades of Vector styrenic block copolymers double as compatibilizers and aid in alloying dissimilar plastics. Proprietary technology reportedly allows an unprecedented level of control over polymerization. It can achieve 100% conversion to triblock copolymer, eliminating uncoupled diblock that can adversely affect tensile strength and elastic modulus of a neat polymer, as well as cause a negative effect on the degree of compatibilization of dissimilar materials. The process also makes it easier to predict molecular weights and eliminates byproduct production of halide salts, cutting out the risk of future discoloration or property degradation. The process also makes it feasible to tailor the polymer block interfaces, opening up the possibility of improving blending compatibility with other polymers.

Dexco is developing a Vector 6000 series of SBS copolymers for modifying polyolefins, styrenics, engineering thermoplastics, recycle blends and alloying.


Offers chlorinated polyethylene, used as a weatherable modifier for rigid vinyls.


Manufactures several types of elastomers for use in improving impact properties of thermoplastic resins. Keltan EPDM and EPR are used in polyolefins, and NYsyn NBR products and Copo SBR products in styrenic thermoplastics. NYsynblak NBR black masterbatches used as combination impact modifiers and black concentrates for ABS and nylon. New Keltan products include:

* Keltan DE259 for applications requiting high impact strength particularly at low temperatures. Homopolymer polypropylene can be upgraded to impact copolymer grade properties. Recycle streams can be upgraded. Product can be mixed at the machine side. TPO level performance can be easily attained.

* Keltan DE292 for applications requiting improved impact strength without undue loss of hardness or tensile strength. Recycled polyolefin can be upgraded to TPO level performance. Product can be mixed at machine side.

EPDMs cover a range from semi-crystalline to amorphous types, and low to high Mooney viscosity. Oil-extended terpolymers available in high and ultra-high molecular weights for high-hardness applications and crosslinked thermoplastic elastomers. Functionalized EPM products also available for engineering thermoplastics. Most products available in pellet and bale form. Pelletized amorphous grades supplied in customized masterbatches.

Customer Applications Development Center (CADC) equipped with full range of applications testing and formulating apparatus for thermoset rubber and thermoplastic/elastomer compound evaluation.


Company's toughening technologies involve four major families of modifiers: ethylene terpolymers, ionomers, grafted polyolefins, and elastomers.

Ethylene terpolymers provide impact resistance over a broad temperature range and particularly at low temperatures for a wide variety of thermoplastics and thermosets. In thermoplastics, ethylene terpolymers are said to offer excellent potential for improving the impact resistance of PVC, ABS, SAN, SMA, thermoplastic polyesters (including recycled materials) and polycarbonate. In PVC they offer two key benefits in addition to higher impact: improved weatherability, and easier processing resulting from a reduction in melt viscosity. Weatherability is also improved in ABS. Thermoset applications include phenolics, polyesters and epoxies.

Surlyn ionomer resins provide low-temperature impact properties in nylon 6. In TPOs, ionomers enhance abrasion resistance and paintability.

In reinforced PP and PE compounds, Fusabond anhydride-grafted polyolefin modifiers improve toughness by increasing adhesion between reinforcements and the resin matrix. Another polyolefin, VLDPE (very low-density PE), has potential as a low-cost toughener for filled and recycled PE materials.

In SMC and BMC, Neoprene rubber functions as both a low-profile additive and impact modifier.


Offers Metablen C series of MBS impact modifiers for rigid PVC. A patented manufacturing process reportedly ensures consistency from lot to lot. Products are sanctioned by FDA as an additive for food-grade PVC. Each product is designed for specific applications, with no detrimental effect on heat stability, and is low in gels.

Also offers Durastrength 200 weatherable all-acrylic modifier for rigid PVC.


Expancel expandable thermoplastic microspheres, used as blowing agents and low-density fillers, find applications as an impact modifier for thermosets and elastomers.

Expancel microspheres create a syntactic foam with defined pore size, closed-cell structure and resilient voids. The resilient nature of Expancel allows deformation without breakage, thereby improving impact resistance and reducing stress. Further applications are found in elastomeric materials where the resiliency of Expancel improves compatibility between filler and binder material.


Exxelor polyolefin-based polymer modifiers can be used to improve the end-use performance of a variety of thermoplastic resins. Exxelor modifier grades are available to improve both low-temperature impact down to -40 F and room-temperature impact properties.

A group of products in this family are functionalized and can be used to modify engineering thermoplastics, polyolefins, glass-reinforced and filled compounds, and alloys or blends of engineering thermoplastics and polyolefins.

Exxelor modifiers reportedly possess excellent thermal stability and long-term heat and weathering resistance, and can be used as modifiers and compatibilizers for engineering thermoplastics.

PO 2011 and PO 2021 improve impact and heat distortion of mineral- and glass-reinforced PP. At levels between 3% and 5%, the grades are said to improve heat-distortion temperature of reinforced PP by up to 45 [degrees] F. Both modifiers can also be used as compatibilizers in homopolymer and copolymer blends of PP and nylon up to a 50:50 ratio.

Bromo XP-50 elastomers have potential applications in impact modification and blend compatibilization. They are based on brominated copolymers of isobutylene and paramethylstyrene, which have a unique combination of good ozone resistance and heat stability, as well as chemical reactivity. These polymers, with or without further modification, have potential as reactive low-temperature flexibilizers and impact modifiers for urethanes, epoxies, nylon, PPE, TP polyesters, and other engineering thermoplastics. Bromo XP-50 polymers also can be used in dynamically vulcanized TP elastomer alloys with polyolefins. In addition, their ability to form grafts, including in-situ grafts, with many polymers suggests utility as compatibilizers for polymer blends.


Stereon block copolymers of styrene and butadiene are used for impact modification of thermoplastic resins. Stereon 721A and 730A are effective graft bases for impact enhancement of high-impact PS and ABS. Products are available in baled form and are usually incorporated directly into the polymerization stream. Stereon 840A is a pelletized, multiblock copolymer that, when dry-blended with PS, PP or PE resins, will improve impact, flexibility, and tear strength. Stereon 840A can be used to upgrade regrind streams and provide impact improvement for degradable plastics. Stereon 900 is a high-styrene, pelletized copolymer designed to be dry-blended with 40-50% crystal PS for extrusion and thermoforming of disposable drinking cups, packaging and medical devices.


Produces impact modifiers for PVC and other resins:

* Blendex 336 and Blendex 338 high-efficiency ABS impact modifiers contain a high percentage of rubber. Blendex 336 provides transparency and is also used in specialty PVC applications where a high degree of stress whitening is desired. Blendex 338 is more efficient than 336 and provides the best low-temperature toughness.

* Blendex 405, 424 and 467 ABS modifiers toughen the polymer without detracting from its optical properties. Used primarily in clear PVC fill and bottles, it can also be used in engineering thermoplastics. In addition to PVC, Blendex products can be used to modify and toughen other polymers such as polycarbonate and polyesters.

* Blendex 702 and Blendex 703 high-heat impact modifiers based on alpha methyl styrene are used to upgrade PVC compounds and other polymers having marginal service-temperature performance.


Produces MBS, ABS and acrylic impact modifiers for PVC and other thermoplastic polymers. Products include:

* B-11A, B-31, B-51, B-511 and J-150 with good impact, excellent stress whitening resistance; excellent clarity in PVC formulations.

* B-22,B-52, B-522, B-521, B-28A, B-38A, B-58A, B-382, B-582, J-210 and J-250 with superior impact, good stress whitening resistance and clarity.

* B-56, M-511, M-521, FM-10, F-20 and FM-23 with outstanding impact and moderate stess whitening properties with opaque behavior in PVC. FM-10, 20 and 23 are also weatherable modifiers for applications requiring UV resistance.


Baymod A ABS powder modifiers, including products for both rigid indoor and exterior weatherable applications, provide improved impact resistance and heat-distortion temperatures for PVC alloys used for injection molding and extrusion. Typical applications include business-machine housings, profile extrusions, and semi-flexible or rigid calendered thermoformable sheets.

Baymod ethylene vinyl acetate copolymers can be used as weatherable impact modifiers for rigid vinyl extrusions such as window profiles, or as "permanent plasticizers" for flexible compounds that require improved extraction resistance and aging properties.

Experimental grades of ethylene-propylene elastomers include Polysar EPM XF 004 that improve flow characteristics and gloss in automotive polyolefin blends and provide impact-modified PP and TPOs with better surface characteristics and gloss. EPDM XG 006 is reportedly the first pelletized, oil-extended synthetic rubber and intended for use in TPOs requiring low stiffness and high flow. Company says its most unique property is its use of paraffinic oil with only 0.5% aromatic content--a factor that improves uv and oxidation resistance and color integrity.


Produces impact modifiers for ABS, HDPE, PP, PVC, and PS/ABS blends.

Novalene EPDM rubber used by molders and PP, PE compounders comes as a dry-blend. Novalene added in prescribed amount, even to scrap, can raise Izod levels to the no-breaking point, even at very low temperatures. Generally, the Izod impact strength of pure Novalene is no-break at -20 F. Will convert low-end regrind homopolymer polypropylene into high impact copolymer, as well as TPOs.

Novalar high-butadiene ABS powder for PVC adds impact strength and processability with less loading. Novalar P, a high-rubber-graft impact modifier for ABS and PVC comes in a free-flowing pellet concentrate that disperses adequately in single-screw extruders, allowing for the incorporation of rubber into SAN to formulate ABS materials.


Ricon liquid 1,2-polybutadienes and 1,2-polybutadiene-styrene copolymers are for use as low-temperature impact modifiers in polyolefins, styrenics and TPE. Applications in PP, peroxide-cured PE, as crosslinking polymers, and in TPE.

Provides Ricopoxy epoxidized (graft) polybutadiene at 6.5% by weight. Epoxy on backbone for use as PVC stabilizer (plastisol).


Paraloid impact modifiers for vinyls and engineering plastics include:

* Paraloid KM-300 series--all-acrylic weatherable impact modifiers for vinyl extrusions subjected to outdoor exposure.

* Paraloid BTA series--MBS impact modifiers for toughening PVC sheet, film and containers used in clear or opaque packaging.

* Paraloid HT series--acrylicimide-based modifiers for improving heat-distortion properties of both clear and opaque vinyl.

Also offers Paraloid EXL impact modifiers designed for engineering resins:

* EXL-3300 series--butyl-acrylate-based tougheners for polyesters and blends, PC and nylons.

* EXL-3600 series--MBS-based impact modifiers with high thermal stability for PC, PET, PBT, and blends.

* EXL-4000 series--imide-methacrylate products for blending with nylons, PC, SAN, ABS and polyesters.


Elastomers Business Center provides SBS and SEBS block copolymers for impact modification of PS, engineering thermoplastics, and alloyed products.

SBS Kraton D polymer series is used for modifying polystyrene, PPE blends and polyolefin blends. SEBS Kraton G polymer series is used for impact modifying of PPE blends and polycarbonate. Kraton G 1901X, a functionalized polymer, is used for impact modification of engineering thermoplastics and for making polar and nonpolar polymers compatible.


Several types of specialty synthetic rubbers include Nipol nitrile rubber (NBR), Zetpol hydrogenated nitrile rubber (HNBR), Hytemp polyacrylate (ACM), Hydrin epichlorohydrin (ECO) and Parel propylene oxide polymer (PO).

Specific grades are tailored for use as impact modifiers, plasticizers, processing aids and lubricants. Typical resins using these additives include flexible and rigid PVC, ABS, nylon, TPEs, blends/alloys, epoxies and phenolics. Applications include calendered and extruded PVC, wire and cable, pipe, molded machine housings, aerospace and industrial composites, and friction products.
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Title Annotation:Manufacturing Handbook & Buyers' Guide 1994/95
Publication:Plastics Technology
Article Type:Directory
Date:Jul 15, 1994
Previous Article:Flame retardants.
Next Article:Lubricants and processing aids.

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