Engineering polymer resin blends

Since the early discovery of miscibility between the low-cost polystyrene and PPE, several commercial grades of PPE/HIPS have been developed, which offer a wide choice of heat resistance (DTUL), impact strength, and melt processability (Cizek 1969 Fried et al. 1978). This versatility of PPE/HIPS blends led to their unparalleled commercial success, accounting for nearly 50 % of market volume of all engineering polymers commercial blends. PPE/HIPS blends filled the price-performance gap between the styrenic resins (HIPS, ABS) and the engineering resins such as polycarbonate, polyarylate, and polysulfones. The technology of PPE/HIPS blends has already been discussed previously under the styrenic blends section (Sect. 19.3), and the typical blend properties are shown in Tables 19.6 and 19.32. 

Fluoropolymers are notoriously immiscible with any other polymer. Usually, they are dispersed in blends of engineering and specialty polymers either to improve processability or to induce lubricity and abrasion resistance. Examples of the PC/Specialty resin blends are listed in Table 1.68. 

The modern tendency is to develop polymer blends that will preserve the desired performance characteristics upon reprocessing. Pew examples of commodity and engineering resin blends are given below. More detailed discussion can be found in [Utracki, 1989a 1998]. 

In the following text examples of recycled polymer blends will be given, first for the commodity, then for the engineering and specialty resin blends. Whenever possible, the methods of compatibilization and re-compatibilization should be the same. In particular, when recycling is to reproduce the original blends performance, the same compatibilization method is essential. For this reason, support of the blends manufacturer should be ascertained. 

BCC Research (2013), cited at http //www.bccresearch.com/market-research/plastics/engineering-resins-polymer-alloys-blends-pls020c.html... 

Engineering polymer blends (EPB) can be roughly divided into blends of an engineering plastic or resin (ER) with a commodity plastic, blends of an engineering plastic with another engineering plastic, blends of an engineering plastic with an elastomer and, blends which contain three or more polymers. We can therefore get combinations such as PPO/PS PPO/PA PC/ABS PET/PBT PBT/PC/SAN etc. each of the blends may in turn be filled. When blends are made the objective is to simultaneously optimize blend formulations, in respect of several properties important for a particular application, sacrificing those which are not important. 

A new polymer modification process has been developed to reduce the cost of the engineering resin. The modification process is blended polymers. A blended polymer is a mixture of at least two polymers or a copolymer. There are three types of blended polymers miscible, immiscible, and compatible polymers. On occasion, blended polymers have properties that exceed those of either of the constituents. For instance, blends of polycarbonates (PC) resin and polyethylene terephthalate (PET) polyester were originally created to improve the chemical resistance of the PC. This is because PC actually had a fatigue resistance and low-temperature impact resistance that was superior to either of the individual polymers. 

Blends comprising a sulfone polymer with other engineering polymers pose a bigger challenge as the compatibility issues are more com-phcated. Miscible blends between sulfone polymers and polymers from other famihes of resins are extremely rare [34 1]. The blend of PPSF and PEI (e.g., Ultem 1000) is a notable exception, as this blend system... 

Semi-IPNs include the early polymer blend of phenolic resin combined with natural rubber to yield improved toughness for phenolic based compositions. With the addition of sulfur, simultaneous IPNs have also been reported. The addition of engineering polymers (PSF, PES, PPO, PEI) to epoxy illustrates a more recent area of research, involving systems classified as semi-IPNs. The phase separation and morphology of PEI/epoxy semi-IPNs was reported by... 

In more added value applications, PLA has attracted much attention as biosotuced material melt blended or not with petroleum-based polymers. For example, PLA-based master-batches have recently been developed by Sukano for dispersion within engineering polymers such as PMMA PC, and ABS to increase their mechanical performances as weU as their biosourced content. Fujitsu and NEC have recently commercialized green notebooks and cell phones based on PLA. Pioneer Corporation has developed flame-retardant PLA resins for the front panel of its DVD drivers. " ... 

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