PE-PMMA

The usually reported second largest market for plastics is building and construction consuming about 20 wt%. However, the amount of plastics is only about 5% of all materials consumed in building and construction so that a large growth area exists for plastics when the price is right since then-properties provide durability, performances, insulation, cosmetics, etc. (Fig. 4-5). Different plastics are used that include PVCs, PEs, PMMA, PSs, phenolics, TS polyesters, and many more. Examples of products are listed in Table 4-1. 

Group 4 metallocene catalysts are also applicable to the above sequential block co-polymerization method to furnish polyolefin and polar polymer block co-polymers. Frauenrath et al. and Chen and Jin " reported the synthesis of PE-/ -PMMA and PP-3-PMMA, respectively, using metallocene catalysts (e.g., raz--(C2H4)(Ind)2ZrMe2/ B(C5F5)3, iPP-/ -iPMMA PP segment 4/ = 8900, PDI= 1.90 block co-polymer 4/n = 10900, PDI = 1.66, MMA content = 17.1 mol%). 

Fig. 17 Synthetic route of PE-PMMA polymer hybrid by RAFT polymerization method...

Fig. 18 TEM images of polymer sheets a PE-PMMA purified polymer (PMMA contents 23wt%), b homo-PE/homo-PMMA blended polymer (homo-PE/homo-PMMA = 75/25 wt ratio)...

Block copolymers with materials such as a polyester (PE) (qv) can be prepd by the reaction of diisocyanate-terminated polyesters with hydroxyl-terminated PMMA according to Wilkes and Grezlak (Ref 21). The basic structure was found to be PMMA-PE-PMMA, with a mw of from 7500 to 47000. The purpose of the work was to produce a stronger copolymer (in terms of stress-strain) by tailoring the amt of each monomer used to produce the copolymer Further information on polymerization can be found in Refs 2a 6a... 

Some synthetic examples of polyolefin hybrids are shown in Figure 2. RAFT polymerization of PE-/-CTA for MMA was initiated by AIBN in toluene at 60 °C. PE-/)-PMMA (PMMA contents 23 wt%) was successfully obtained . PE-/)-PMMA having the contents of PMMA (73 wt%) was yielded from PE-g-Br by ATRP for MMA with RuCl2(PPh3)3/Bu2NH as a catalyst. ATRP for acrylonitrile/styrene using PP-g-Br as a PO-MI was carried out to produce PP-g-AS (poly(acrylonitrile-co-styrene)). Then, EBR-g-PS was obtained from EBR-g-Br as a PO-Ml by ATRP for styrene. By selecting the kinds of PO-MIs and polar monomers for CRP, various kinds of PO hybrids have been obtained. 

Figure 7(c) shows the phase stmcture of the blend polymer composed of EBR/PLA (15/85 wt%). Macro-phase separated EBR domains in the PLA matrix were observed. By adding 5 wt% of PE-/ -PMMA (PMMA contents 75 wt%) to EBR/PLA (10/85 wt%) as a compatibilizer, finely dispersed EBR domains are observed in Figure 7(d). As a result, this polymer indicates very high Izod impact strength value (378 J/m) vis-a-vis the blend polymer s value... 

PE/PMMA dynamic and steady state Matinez Williams,... 

Figure 9.10 Thickness profile of crazes in PES, PMMA, PC and plasticised PVC, fitted by the prediction of Dugdale s model (from Doll, W, Adv. Polym. ScL, 52/3, I 19, 1983, Springer Verlag). The vertical scale is exaggerated.

Ycfor PE, PMMA and PS are in agreement with the values measured by Dann (7) (see Table 2). Using the adhesion properties shown in Table 5 and the relationships listed in Table 1, we can determine the work of adhesion and spreading characteristics of polymer-polymer systems. 

Suitable polymers NBR, PE, PMMA, PS, PVAc Piunova, V A Hogen-Esch, T E, Polymer, 69, 58-65, 2015. 

Suitable polymers - PA6, PA11, PC, PEEK, PET, PES, PMMA, PS, PVCA ... 

Following optimisation of the channels, it was confirmed experimentally that the following plastics could be injected ABS and glass fibre, ASA, CA, EVA, PA and glass fibre, PE, PMMA, POM and glass fibre, PP and glass fibre, PS, soft PVC, SB, SAN and glass fibre. 

To evaluate the capabilities of the system, a polymer blend comprising PE and PMMA homopolymers and a PE/PMMA copolymer was prepared and analyzed. The molar masses of PE, PMMA and the copolymer were = 1,100 g/mol, = 263,000 g/mol and = 10,600 g/mol, respectively. The experiments were performed with TCB as the mobile phase. WET suppression was applied to the intrinsic solvent signals, i.e., the three aromatic proton signals were suppressed. 

Fig. 16 SEC-NMR (400 MHz) on-flow run (corrected) of a PE-PMMA-copolymer blend at 130°C in TCB. (Plow rate 0.5 mL/min, concentration 2 mg/mL of each polymer, 300 pL injection volume, 5 Waters columns, 24 scans per PID, 1.24 s repetition delay.) (Reprinted from [130] with permission of Elsevier Limited)...

In the second experiment, the CCD of the PE/PMMA copolymer was investigated by using on-flow and stop-flow experiments. The distributions of the different structural moieties corresponding to MMA and ethylene can be seen and correlated with the corresponding molar masses. The quantification of the chemical composition based on the on-flow data is presented in Eig. 18. It shows that the MMA monomer units are mainly distributed at higher molar masses. 

Fig. 18 Monomer composition of PE-PMMA copolymer vs. retention time...

The analysis shows that when an essential difference in adhesion of polymer components of a blend to CB takes place (PE + PU, PE + BNR, PE + PMMA, PE + PCP, PS + PMMA), CB moves to the interface only from the phase characterized by lower adhesion to CB. 

The ratio of polymer viscosity values, imder which a substantial drop in local interfacial CB concentration is observed, differs for various polymer pairs. The greater is the difference in wetting forces of polymers, the more times the viscosity of the second (having higher wetting force) polymer, can exceed the viscosity of the preliminarily filled polymer. So, this ratio is about four for the PE + PMMA blend, and about two for the PS+PE blend. The best conditions for particles to localize at the interface are provided when viscosity of the second polymer is slightly lower than that of a preliminarily filled polymer component. 

SANS measurements on blends of PVME/PS have been reported in a number of studies [187-192]. PS/PVME is a widely studied blend, at least partly due to the lest behavior well-documented by various characterization methods. The results show miscibility in the region classified as single phase by more conventional methods. The difference in the lest temperature ( 40 °C) of deuterated PS/PVME versus PS/PVME blends was noted, yielding a relatively small effect, thus justifying the use of deuterated polymers to model hydrogenated polymer blends [187,192]. Additional SANS studies include PMMA/PVF2 [187], PS/P(nBMA) [189], PB(different vinyl contents)/PS [193],polyaniline/PA6 [194] and chlorinated PE/PMMA [195] blends as well as citations noted in Table 5.1. 

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