Several new developments were discussed at the Profiles 2007 conference held in USA. The notable ones include: High melt strength polyolefin elastomers for use as ingredients in TPO compounds that can compete with TPVs and flexible PVC. The conference also presented new PVC alloys that boast superior heat resistance and weatherability in dark-colored profiles. Another new product highlighted was a compatibilizer based on new chemistry that reportedly outdoes previous products at improving the physical properties of mixed recycle streams containing mainly polyethylene.

Three new grades of high-melt-strength (HMS) polyolefin elastomers (POEs) are recommended for use in TPOs for extruded profiles, thermoformable sheet and blow molding. These POEs are made with Dow�s Insite metallocene catalyst to produce a high degree of branching in the reactor. The result is said to be soft materials with enhanced melt strength. When used in blends with HMS PP, fillers and plasticizers, they can produce soft TPOs with excellent extrusion processability and rapid set-up, comparable to TPV and flexible PVC. They are expected to require much lower extruder torque (power consumption) than conventional olefin elastomers or PPs. In addition, finished products are reported to have smoother surfaces and controlled gloss. The first of these elastomers, Engage 7387 (0.87 g/cc density, <0.5 MI, and 88 Shore A hardness), introduced three years ago, is now commercial. So far, it is attracting the most interest in low-gloss automotive soft sheeting and thermoforming applications, although it can be used in profiles.
Developmental ENR 7086.01 is a high-melt-strength ethylene-butene copolymer that boasts a high level of long-chain branching and a relatively broad MWD. It has been used alone and for modifying PP homopolymers and copolymers for blow molding, extrusion and thermoforming. Potential applications include beverage tubing and blow molded bellows.
Excellent extrusion rates and fast setup are said to make TPOs with Dow's new high-melt-strength (HMS) polyolefin elastomer (POE) grades competitive with TPVs and flexible PVC. These profile components contain 20-40% POE in HMS PP. Developmental ENR 6386 is Dow's new premier grade for profiles when paired with HMS-PP in a TPO compound. This is the most highly branched grade and shows excellent shear-thinning rheology, which reportedly enables very high extrusion speeds comparable to those for TPV or PVC. This modifier (0.875 g/cc, 0.5 MI, 75 Shore A) can be mixed with 20-40% HMS PP by batch or in-line compounding to achieve upper service temperatures between 80 degree C and 120 degree C. It can replace flexible PVC and TPVs in applications not needing compression-set performance.

PolyOne Corp. unveiled a new line of PVC alloys claimed to offer exceptional heat resistance without warping or sagging, as well as superior weatherability for dark-colored profiles in all climates. Also cited are better flow and a lower specific gravity than competitive products, which leads to lower part weight. The new Geon HTX Ultra compounds are applicable for use as solid profiles or weatherable cap layers. They are aimed at windows, fences, decking, railings, siding and other construction profiles. PolyOne�s new Geon HTX Ultra PVC alloys show better color stability than conventional PVC window-profile compounds, as indicated by smaller delta L values. Geon HTX Ultra products are also said to outperform conventional high-heat PVC and CPVC compounds, while being "process-friendly." PolyOne presented results of accelerated and outdoor weather testing in which black, dark brown, and dark green profiles made with Geon HTX Ultra showed less color shift. Outdoor testing was conducted in Arizona, Florida, and Ohio. The last is noteworthy because it is representative of the northern industrial climate, which has proven to be extremely harsh and difficult for traditional PVC profiles to maintain their color properties.

Owing to its improved effectiveness over traditional maleic anhydride (MAH) grafted polymers, a unique additive that compatibilizes PE-based recycle streams for use in plastic lumber and other products is making headway in the market. DuPont's Fusabond E EC-603D, which first arrived a year ago, is an anhydride-functional ethylene copolymer. It's role is to improve the interface between a non-polar polymer such as HDPE, LLDPE or LDPE and a polar polymer such as EVOH and nylon. Because its functionality is built into the polymer backbone, rather than grafted on after polymerization, this copolymer has significantly higher anhydride levels, which provide more reactive binding sites. As a result, this additive has a wider operating window for coupling with EVOH, moisture, lubricants, nylon, and fiberglass, which allows users to buy cheaper recycle vs. more costly "cleaner" reclaim.

A highly thermally insulating as well as cost-effective window system has been introduced using specially developed Ultradur® High Speed (PBT) by BASF. This glass fiber-reinforced thermoplastic replaces the steel that is normally used for window frame profiles, thus providing much better heat-insulating features without changing the mechanical properties of the windows. The new profiles do not only save time-consuming and costly work steps for window manufacturers but also weigh 60% less than their metal counterparts. The new window profiles can be processed on conventional production lines. Thermal insulation improved by 20%. Window manufacturers can process the new profiles on their current equipment without the need to make additional investments.
Two flat strips made of Ultradur are extruded into the new window profile, replacing the metal profile that is usually heavy and difficult to install. The U-value (formerly "k-value": heat transfer coefficient, thus a parameter for thermal-insulation capacity) of the window frame profiles using the flat Ultradur strips is improved by about 20%, namely, to 1.1 W/(m� . K), in comparison to the standard versions that contain a steel profile.