Masterbatches carriers

It might seem axiomatic that the various polymers of ethylene discussed above should be miscible indeed, recently it was recommended that blends of HDPE and LDPE be used to obtain properties intermediate between those of the homopolymers. However, work in several centres has shown that miscibility is the exception rather than the rule even blends of LDPE and LLDPE tend to become unmixed into separate crystalline phases. This sounds a warning concerning masterbatch carrier polymers it is not prudent to use a LDPE or, worse, an EVAC copolymer as carrier in a masterbatch introduced into matrices of HDPE and LLDPE, or, worse, polypropylene. It may apparently... 

Characteristic Stabaxol KE 8993 is a polycarbodiimide-masterbatch carrier polymer Nylon 6 (PA6)... 

Stabaxol KE 9193 is a polycarbO(diimicle-masterbatch carrier polymer Polybutyleneterephthalate (PBT)... 

A masterbatch is developed using best elastomers from the Dow to control the CLTE and shrinkage of the D143.00 at the injection molding machine. The talc level in the talc masterbatch is maximised to 70-75% talc and only 25-30% masterbatch carrier of a INSiTE type elastomer. This masterbatch carrier allows easy dispersion of the talc at minimum let down ratio (LDR). 

Pigments are classified by an internationally recognised convention, published in the International Colour Index by the Society of Dyers and Colourists in Bradford, in association with the American Association of Textile Chemists and Colorists. The Index issues a generic name to chemically identical products (e.g., titanium dioxide is classified as C.I. Pigment White 6). Where structures are known, pigments are also given a constitution number (e.g., titanium dioxide has the constitution number Cl 77891).This number is reserved for the essential colorant, other ingredients, such as the carriers used in a masterbatch, do not affect this classification. 

The MFR for the PP resin and the masterbatch colorant were measured to see if the masterbatch material met the criteria defined by Benkreira and Britton [28] and as discussed in Section 8.6. The MFRs were 20 and 116 dg/min (230 °C, 2.16 kg) for the natural PP resin and the masterbatch colorant, respectively. Obviously, the color concentrate masterbatch was not well matched for the natural PP resin according to the guidelines developed by Benkreira and Britton. That is, the carrier resin used to make the masterbatch was too low in viscosity to break up pigment... 

In plastics, relative viscosity can be defined as the ratio of the viscosity of a concentrate to that of the neat carrier polymer at the same temperature. In this use, relative viscosity predicts relative jetness—defined in the same manner—more accurately than the carbon black loading in a concentrate. A mismatch between masterbatch and letdown viscosities causes incomplete mixing and is the reason that relative jetness can decrease with an increase in relative viscosity [5]. 

The pigmentation of Polymethyl Methacrylate (PMMA) and ultrahigh-molecu-lar-weight polyolefins presents familiar difficulties. Due to the high difference in viscosity between the pigment concentrate and these polymers, it is sometimes necessary to use special masterbatches based on high-molecular-weight carriers. 

A typical masterbatch for extrusion, injection, or blow molding would consist of an appropriate carrier resin for the polymer being processed, a fluorescent pigment, and a wax additive. The following example illustrates a 25% color concentrate formula for injection molding which should be let down at 4% to yield a final color loading of 1% ... 

Companies will custom formulate colorant and additive products designed to be used by plastic molders, who will, in turn, produce the final consumer products. The raw materials for colorant and additive products may be in powder, liquid, or solid form. The products formulated from them may also be in powder, liquid, or solid form. Dry color formulations (powder form) currently comprise less than 5% of the total colorant and additive products being produced today. Liquid formulations account for another 5% however, this form of product is increasing in popularity and is expected to capture a larger share of the colorant and additives market in the near future. The solid form, known as concentrates or masterbatch products, are concentrated ingredients encapsulated in a carrier resin that is usually in pellet form. This type of product comprises the overwhelming majority of the formulated products used by molders and compounders today. A discussion of the basic production processes associated with the production of the various colorant and additive product types is presented below. 

JMAC antimicrobial masterbatches are described. The products are based on the controlled release of silver ions. A silver chloride/titanium dioxide composite particle releases silver ions on contact with water and then maintains an equilibrium concentration in solution, releasing more ions as required to give effective preservation. Its antibacterial performance in PP mouldings, in thin section PE, itylon, PETP and PP fibres is reported. JMAC masterbatches are available in most polymeric carriers including PE, PP, polystyrene, ABS, PETP and nylon, with typical addition rates of around 1%. 

Solid masterbatching consists of a high concentration of pigment in a carrier. The carrier can be the plastic with which it is to be compounded, a similar plastic or low molecular weight carriers. The ideal is a masterbatch which is miscible and dispersible with all types of plastic. The pigment level has conventionally been 10-20%. Recently more concentrated masterbatches with 40-60% pigment, usually in a carrier, have been made for use at an approximately 1% addition level. 

While masterbatching systems have received little attention to date, there is now awareness of the importance of various constituents such as carriers of a similar plastic but of a different MFT, different types of plastic, paraffins, oils, etc., and certain added lubricants, etc. Even though they are present at low levels after dilution, knowledge is becoming more relevant. As an important step in knowing the constituents of a plastic, details on the master batch should therefore be included. Using a reputable masterbatcher (i.e. one aware of pharmaceutical concerns) overcomes the above risks. 

The converting or moulding process may also include the use of processing aids, e.g. lubricants and mould release agents. Masterbatching may contain lubricants, mould release and a carrier or base diluent which assist the manufacture of a concentrated masterbatch containing colourants. 

Hubron. ubronLtd.] Carbon black in SAN, LI)PE, PP, or PS carrier black masterbatch for compounding, molding, film, sheet extrusion. 

Piasbiak . [Cabot Plastics Ltd.] Carbon or furnace black masterbatt witii polyethylene, EVA, polypropylene, polysty e, or SAN carriers black masterbatch for molding and extrusion of articles for pkg., electronic equip, cases, radios, TVS, domestic appliances, pipe and sheet, film, cable sheathing. 

Plaswite . [Cabot Plastics Ltd.] Uta-nium dioxide masterbatch in polyethylene, polypropylene, or pdysQnene carriers some widi Udiopone or caldum catbcmaie as extenders white master-beach for blown andcast film, faij. moldr ii, blow mdding of drug, cosmetic, and food containers. 

Caibodilite E is a masterbatch of 10wt% carbodiimide in a PET carrier resin. 

Additives are incorporated into polymers several ways the resin supplier may include them in the raw material, an intermediate compounder may produce additive-enhanced feedstock, or the final extrusion processor may add them directly. When incorporated in final processing, additives maybe introduced individually or as part of a masterbatch, a blended compound containing one or more additives in a polymer carrier. A masterbatch material is incorporated most efficiently when its carrier is compatible both chemically (same polymer) and Theologically (same flow characteristics) with the primary resin. 

PR-5104 containing 66% bromine is a dust-free, 100% active FR masterbatch for engineering plastics. It is based on the company s experience of high-molecular weight polymeric brominated FRs as carriers. This material provides good processibility, high temperature resistance and outstanding compatibility between fibre reinforcement and the resin matrix. 

Color Concentrate (Masterbatch). Expert compounders disperse colorants at 20 to 60 percent concentration in a carrier polymer, using high shear to break down agglomerates and produce uniform dispersion of maximum coloring efficiency. This color concentrate is used by processors, simply blending it with virgin (natural color) resin ( letdown with natural ). Typical ratios of concentrate/natural are 1/20 to 1/100. This technique is low in cosL does not create inventory problems, and is most commonly used with commodity resins. 

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