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Different technologies to prepare long term pesticide forms include polymer coating, preparing composites and encapsulating pesticides in nanoparticles. A simple and low-cost method was proposed to obtain slow-release formulations by co-extrusion of a pesticide with a biodegradable polymer at a temperature above the melting points of both components. A herbicide metribuzin and low-melting polyester poly-ε-caprolactone were chosen for this work. Formulations containing 10%, 20%, and 40% herbicide were prepared. During 7 days of their exposition in water, it was released from 81% to 96% of initially loaded metribuzin; the highest release was detected for 40%-loaded forms. Biodegradation of the constructs and pesticide release were further studied in the model soil. Degradation rates of the specimens increased with an increase in pesticide content, from 9% to 20% over 14 weeks for the 10%/20%-loaded and the 40%-loaded specimens, respectively. The release of metribuzin reached, respectively, 37-38% and 55%. The herbicide content in soil was lower due to its partial degradation in soil; it reached 23-25% and 33%, respectively, from initially loaded into the polymer matrix. Release kinetics of metribuzin in water as in soil best fitted the First-order model. The used approach is promising for obtaining long-term release formulations for soil applications.

This study aimed to evaluate the protective effect of flaxseed mucilage on the co-extrusion microencapsulation of Lactobacillus rhamnosus GG. Core flow rate, chitosan coating, and flaxseed mucilage...

Results of computer modeling of the process of co-extrusion of two-layer ring profile insulation in extrusion dies by the finite-element method are presented. Design features of the 3D models are specified. Recommendations for obtaining high-quality products are presented.

The scientific article presents a physical model of the technical process of co-extrusion processing of secondary polymeric materials. A set of tools for automated control and monitoring of the model is considered, which allows to adjust smoothly the values of the rotational speeds of screws of extruders, the temperatures in the material heating zones and the pressure at the outlet of the co-extrusion head. The results of experiments to determine the temperature of the parison over a cooling time and the effect of screw speed and pressure in the head on the quality of mixing components are given. The results obtained by physical modeling confirm the correctness of the authors' calculations performed using the proposed mathematical models. Thus, it is possible to continue research in this direction, the result of which will be new designs of co-extrusion equipment, allowing to process efficiently polymeric waste into new high-quality products.

This study aimed to evaluate the survivability of Lactiplantibacillus plantarum 299v encapsulated in chitosan-coated calcium alginate beads with inulin as prebiotic in simulated gastrointestinal conditions and roselle juice. The concentration of calcium chloride and inulin for L. plantarum 299v microencapsulation was optimised and the survivability of free and microencapsulated L. plantarum was assessed under simulated gastrointestinal conditions. Storage stability of the optimised encapsulated L. plantarum 299v-inulin was determined throughout four (4) weeks of storage in roselle juice at 4 °C and 25 °C. The optimized formula for L. plantarum 299v was 2.0% (w/v) of calcium chloride and 3.0% (w/v) of inulin. Optimized calcium alginate-chitosan L. plantarum 299v microbeads with inulin did not affect (p > 0.05) the bead diameter, with a mean diameter of 685.27 μm, and microencapsulation efficiency of 95%. Encapsulated L. plantarum 299v with inulin showed higher survivability (>107 CFU/mL) than free cells and encapsulated L. plantarum 299v without inulin under simulated gastrointestinal conditions and after four (4) weeks of storage in roselle juice at 4 °C. The results indicate that co-extrusion encapsulation and addition of inulin had improved the viability of L. plantarum 299v in roselle juice by protecting probiotic against unfavourable gastrointestinal conditions and prolonged storage. Resumo O objetivo deste estudo foi avaliar a capacidade de sobrevivência de Lactiplantibacillus plantarum 299v encapsulado em esferas de alginato de cálcio revestidos com quitosana, com inulina como prebiótico, em condições gastrointestinais simuladas e suco de rosélia. A concentração de cloreto de cálcio e inulina para a microencapsulação de L. plantarum 299v foi otimizada e a sobrevivência de L. plantarum livre e microencapsulado foi avaliada em condições gastrointestinais simuladas. A estabilidade do encapsulado otimizado L. plantarum 299v-inulina durante armazenamento foi determinada ao longo de quatro semanas em suco de rosélia a 4 °C e 25 °C. A fórmula otimizada para L. plantarum 299v foi de 2,0% (w/v) de cloreto de cálcio e 3,0% (w/ v) de inulina. Microesferas otimizadas de alginato de cálcio-quitosana contendo L. plantarum 299v com inulina apresentaram diâmetro médio de 685,27 μm sem diferença significativa (p>0,05) em relação às partículas sem inulina, e eficiência de microencapsulação de 95%. L. plantarum 299v encapsulado com inulina mostrou maior capacidade de sobrevivência (> 107 CFU/mL) do que células livres e L. plantarum 299v encapsulado sem inulina em condições gastrointestinais simuladas e após quatro semanas de armazenamento em suco de rosélia a 4 °C. Os resultados indicam que a a encapsulação por coextrusão e a adição de inulina melhoraram a viabilidade de L. plantarum 299v em suco de rosélia, protegendo o probiótico contra condições gastrointestinais desfavoráveis e prolongando o armazenamento.

The complexes [Pt(tolpy)Cl(L)] (tolpy = 2-(4-tolyl)pyridyl; L = dmso, dms, py, PPh3, CO) are precursors for the catalytic cleavage of C–C bonds and extrusion of CO from a series of unactivated keto...

Singly NHC-coordinated (aminoboryl)aminoborenium salts react with Na2 [Fe(CO)4 ] to yield stable coordination complexes of aminoborylene-stabilized aminoborylenes, which exhibit exceptional σ-donor properties. Upon photolytic CO extrusion from the metal center, the diboron ligand adopts a novel η3 -BBN coordination mode, where bond-strengthening backdonation from the metal center into the vacant B-B π-orbital is observed. This bonding situation can be alternatively described as a Fe-diaminodiborene complex. In a related reduction of CAAC-stabilized (aminoboryl)aminoborenium with KC8 , the reduced species can be captured with nucleophiles to form three-coordinate (diaminoboryl)borylenes, where both amino groups have migrated to the distal boron atom. Collectively, these reactions illustrate the isomeric flexibility imparted by amino groups on this reduced diboron system, thus opening multiple avenues of novel reactivity.

One of the varieties of extrusion processing of food products is considered - co-extrusion of high-viscosity masses. Prospects for the development of fish-based co-extrusion products have been determined. Differential equations of motion of two contacting food masses in non-stationary conditions are given. The relationship between the process parameters and the geometric characteristics of the formation unit is established on the basis of the method of mathematical modeling.

In order to reduce the weight of vehicles and their CO2-emissions and to increase driving range, new ways of producing hybrid material compounds must be developed to tailor the properties of the part exactly to the intended use. Lateral angular co-extrusion (LACE) offers the possibility to produce hybrid profiles. In the past, this process was used to extrude flat magnesium-titanium profiles and after further development, co-axial aluminium steel profiles.

One of the routes to minimize the environmental impact of plastics waste is the use of bio-sourced and biodegradable alternatives, particularly for packaging applications. Although Polyhydroxyalkanoates (PHA) are attractive candidates for food packaging, they have poor processability, particularly for extrusion film blowing. Thus, one relatively successful alternative has been blending PHA with a biodegradable polymer. This work proposes film blowing of a co-extruded Poly (hydroxybutyrate) (PHB) layer with a poly butylene adipate-co-terephtalate (PBAT) layer to enhance bubble stability, mechanical and barrier properties. Co-extrusion is detailed, together with the different strategies followed to improve adhesion between film layers and the PHB content in the films. Films with thicknesses below 50 micron and elongation at break beyond 500 % were consistently produced., This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No. 774088. LH also acknowledges funding from the Portuguese Foundation for Science and Technology Investigator Programme through grant IF/00606/2014.

In this work, the numerical simulation of the non-isothermal steady co-extrusion fiber spinning with flow-induced crystallization is explored. The model is based on the formulation originally proposed by China et al. in which Newtonian and Phan-Thien-Tanner (PTT) fluids are considered the core and the skin layer, respectively. The polymeric flow rate fraction, Deborah dimensionless number and the PTTs parameters on the temperature, the velocity and the crystallization profiles are analyzed. The numerical results show: the temperature profile is sensitive to the polymeric layer flow rate and the deformation parameters (shear thinning and extensional), the tensile stress induced crystallization parameter has a strong influence at the onset of the process, increasing drastically temperature and crystallinity.

Various casing types can be used to produce dry fermented sausages. Within the group of dry fermented sausages, efflorescence formation represents a current issue for the meat processing industry. Therefore, this study aims to investigate the coherence between the casing type and the efflorescence amount. Different casing materials (co-extruded alginate, collagen, and natural casing) were used for the sausage production. The sausages were stored under modified atmosphere packaging at 4 °C and visual and chemical analyses were conducted regularly during 8 wk of storage. Image analyses revealed different amounts of efflorescences for the sausages with alginate (72.2%), collagen (48.3%), and natural casings (25.0%). The magnesium content increased in different amounts on the surface of the sausages produced with alginate (88%), collagen (83%), and natural (59%) casing. The calcium content significantly increased on the alginate casings by 32% but the other casing types showed no enrichment of calcium on the surface. It seems likely that the differences regarding the efflorescence formation occur due to differences in the average pore size of the casings.

This study aimed to compare two processes for the encapsulation of Lactobacillus acidophilus LA3 using alginate or a blend of alginate–shellac as the wall material and sunflower oil as the core. The particles were dried and stored for up to 60 days at 25 °C for stability studies, and the survival of the encapsulated probiotics in simulated gastrointestinal fluids was evaluated. The viability of the LA3 encapsulated by co-extrusion using alginate or a blend of alginate–shellac was, respectively, 6.2 and 7.2 log CFU/g (colony-forming units per gram), after 60 days of storage, while the viability of the LA3 encapsulated by extrusion was, respectively, 5.3 and 6.2 log CFU/g. The particles produced with the blend of alginate–shellac presented additional protection to the probiotics, as revealed by the increased survival rates in simulated gastrointestinal fluids. Taken together, these data provide a promising alternative for the incorporation of the probiotic L. acidophilus LA3 into new functional foods.

The concept of smart blender to form a multilayer structure of PLA/EVOH has been developed. Unlike conventional mixing, smart blending provides a formation of multilayer structure by dictating the motion of stir rod to agitate melts. The PLA and EVOH are supplied separately by a single-screw extruder. An experimental rig is assembled at the end of a co-extruder, and melt from an extruder entered an experimental rig via a cylindrical port. The molten EVOH is recursively stretched and folded in an experimental rig of PLA major phase to give an alternating layer structure. The rod is rotated by variable speed motor that is independently controllable. The rod rotational speed and volumetric flow rates of EVOH and PLA are of our interest. Careful design of stir rod in smart blending is necessary for effective performance. The computational model provided the visualization of flow profile inside an experimental rig. The simulation determined the geometry of the stir rod required to achieve the spiral flow developed of the melt. The experimental results suggest that the injected streams of EVOH are stretched and folded to multiple and distributed layers ranging thickness from 10 to 200 um. The characteristic folding of EVOH melt depends on the volumetric flow rate of the screw extruder and rod rotational speed. However, the coalescence of EVOH layers is observed for high rod rotational speed.

Present study was undertaken to optimize the process conditions for development of food grains (maize, defatted soy flour, sesame seed)-banana based nutritious expanded snacks using extrusion processing. Experiments were designed using Box–Behnken design with banana pulp (8–24 g), screw speed (300–350 rpm) and feed moisture (14–16% w.b.). Seven responses viz. expansion ratio (ER), bulk density (BD), water absorption index (WAI), protein, minerals, iron and sensory acceptability were considered for optimizing independent parameters. ER, BD, WAI, protein content, total minerals, iron content, and overall acceptability ranged 2.69–3.36, 153.43–238.83 kg/m3, 4.56–4.88 g/g, 15.19–15.52%, 2.06–2.27%, 4.39–4.67 mg/100 g (w.b.) and 6.76–7.36, respectively. ER was significantly affected by all three process variables while BD was influenced by banana pulp and screw speed only. Studied process variables did not affected colour quality except ‘a’ value with banana pulp and screw speed. Banana pulp had positive correlation with water solubility index, total minerals and iron content and negative with WAI, protein and overall acceptability. Based upon multiple response analysis, optimized conditions were 8 g banana pulp, 350 rpm screw speed and 14% feed moisture indicating the protein, calorie, iron content and overall sensory acceptability in sample as 15.46%, 401 kcal/100 g, 4.48 mg/100 g and 7.6 respectively.

It is of great importance to understand the stretching and folding mechanism in the multiflux co-extrusion die to get uniform multilayer distribution at the end of die lip in the multilayer co-extrusion processes. In this work, to understand the mechanism of the layer distribution, modeling and numerical simulation were carried out for three-dimensional flow analysis in the multilayer co-extrusion die. The multilayer flow fields were numerically visualized and analyzed on the arbitrary cross-section of the multiflux die. In addition, numerical results for the multiflux die characteristics were obtained for non-Newtonian fluids in terms of power-law index for the cross model, which will be useful for the optimal design of screw and die, simultaneously, in the multilayer co-extrusion process.

Encapsulation confers protection to substances as essential oils from processes like oxidation, evaporation or uncontrolled release. In this study almond oil capsules were obtained by co-extrusion/gelling technique. Chitosan was used as shell material and sodium triphosphate pentabasic as cross linking agent. Different encapsulation process variables were studied: cross-linker concentration, nozzles size and potential. Optical microscopy was used to determine the capsules morphology and degradability tests were performed in order to study capsules degradation over time. Results showed that nozzles size and cross linking concentration are key variables to consider in the encapsulation process. Degradability tests showed rapid weight loss.

An unprecedented nickel-catalyzed decarbonylative silylation via CO extrusion intramolecular recombination fragment coupling of unstrained and nondirecting group-assisted silyl ketones is described. The inexpensive and readily available catalyst performs under mild reaction conditions and enables the synthesis of structurally diverse arylsilanes, including heterocyclic and natural product derivatives.

INTRODUCTION: Currently, hot melt extrusion (HME) is a promising technology in the pharmaceutical industry, as evidenced by its application to manufacture various FDA-approved commercial products in the market. HME is extensively researched for enhancing the solubility and bioavailability of poorly water-soluble drugs, taste masking, and modifying release in drug delivery systems. Additionally, its other novel opportunities or pharmaceutical applications, and capability for continuous manufacturing are being investigated. This efficient, industrially scalable, solvent-free, continuous process can be easily automated and coupled with other novel platforms for continuous manufacturing of pharmaceutical products. AREAS COVERED: This review focuses on updates on solubility enhancement of poorly water- soluble drugs and process analytical tools such as UV/visible spectrophotometry; near-infrared spectroscopy; Raman spectroscopy; and rheometry for continuous manufacturing, with a special emphasis on fused deposition modeling 3D printing. EXPERT OPINION: The strengths, weakness, opportunities, threats, (SWOT) and availability of commercial products confirmed wide HME applicability in pharmaceutical research. Increased interest in continuous manufacturing processes makes HME a promising strategy for this application. However, there is a need for extensive research using process analytical tools to establish HME as a dependable continuous manufacturing process.

This work focused on the development of a concentric multi-layered fixed-dose combination via an advanced manufacturing technique, hot-melt co-extrusion. The dosage form was designed to offer differing release behaviour; immediate and sustained release from the coat and core, respectively. Hydrochlorothiazide and losartan potassium were incorporated as anti-hypertensive drugs. Solid-state characterisation revealed that both were transformed into their amorphous forms. In-vitro dissolution testing showed desired release performances offering both immediate and modified release.

Lactobacillus acidophilus NCFM (L-NCFM) was microencapsulated via co-extrusion technique with mannitol. Optimization of coating material, locust bean gum (0% to 2%, w/v) and prebiotic, mannitol (0% to 5%, w/v) was tested on bead size and microencapsulation efficiency. L-NCFM cells microencapsulated in three different forms were tested in simulated gastric juice (pH 2.0) and simulated intestinal juice (pH 7.5) and storage test at 4 °C and 25 °C for 4 weeks. 0.5% (w/v) locust bean gum and 3% (w/v) of mannitol are the optimal concentrations to produce bead size of 570 µm, microencapsulation efficiency of 96.81% and cell count 8.92 log CFU/mL. Microencapsulation of L-NCFM with mannitol protect cells better in acidic environment. The viability of encapsulated L-NCFM with mannitol at 4 °C throughout the storage period for 30 days ranged from 8.62 log cfu/mL to 6.80 log cfu/mL, which met the minimum required for probiotic (106CFU/mL).

Silo bag technology is used for storing grains in a hermetic plastic structure. The major limitation of this structure is resistance to improper handling and external aggression, thus promoting pest incidence due to alterations in its internal atmosphere. In this study, we developed a biopesticidal silo bag consisting of a co-extruded three-layer film made of polyethylene and essential oil of Mentha piperita (7% w/w) in the inner layer. A film with the same structure but without essential oil was produced to be used as a control. The presence of the biopesticide in the silo bag was confirmed by FTIR-spectroscopy. Thus, mechanical, optical and chemical properties were evaluated. Diffusion coefficient of biopesticide from silo bag at 15, 25 and 35 °C was estimated as 6.4 ± 0.1 × 10-11, 1.45 ± 0.17 × 10-10 and 1.30 ± 0.2 × 10-10 cm2/s, respectively. Finally, the biopesticide silo bag was tested against Rhyzopertha dominica, primary pest of stored grain, showing 100 % of mortality during the time assayed (7 days). Hence, the incorporation of biopesticide by co-extrusion technology (low-cost and efficient machinery) into the inner layer of a silo bag could help to replace synthetic pesticides and avoid manipulation of these in the field, preventing biotic infestation.

Proanthocyanins from Chinese bayberry leaves (CBLPs) were co-extruded with rice flour at different concentrations. The physicochemical properties of the restructured rice were analysed with XRD, RVA, and DSC, while the digestibility was analysed with an in vitro digestion model. Results indicated that the extrusion process significantly reduced the degree of starch crystallinity and the addition of CBLPs enhanced this effect. The restructured rice with CBLPs showed higher peak viscosity and lower pasting temperature than those of the samples without CBLPs. With the increasing of CBLPs concentration, the equilibrium hydrolysis of rice starch decreased from 86.61% to 70.89% with a kinetics constant (k) ranged from 7.51 × 10−2 to 4.71 × 10−2 (min−1), indicating a good retardation of CBLPs on starch hydrolysis. Our results indicate that co-extruding CBLPs with rice flour could reduce its starch digestion significantly and be an option for producing staple rice food with lower digestion.

The PP multilayer film/foams prepared by the multilayer coextrusion technique possess a unique solid/porous alternating horizontal architecture, in which the film layers can effectively suppress the premature rupture of cells in foam layers. This paper introduces a strong and lightweight layered cellular structure developed through optimized uniaxial drawing of the coextruded PP multilayer film/foams. Moreover, systematic study reveals the effects of orientation on the structure and properties of the oriented PP multilayer film/foams. Formation of subcellular interconnected porous structure decreases the bulk density with increasing draw ratio (DR) up to DR = 3.5. In addition, strain induced increase in the orientation of α crystals and crystallinity of PP during uniaxial drawing improves the tensile strength and modulus of the oriented multilayer film/foam significantly. The oriented PP multilayer film/foam with the lowest density and improved tensile properties can be obtained at DR = 4 at the optimized...

Mg-3Al-1Zn round ingots were divided into several pieces and then cobbled together to introduce specific interfaces before direct extrusion. The microstructure, texture and mechanical response of the magnesium alloys processed by conventional extrusion and co-extrusion with introducing various interfaces were examined. The results indicated that the prewired various interfaces played important role on the microstructure evolution and texture modification of magnesium alloys during extrusion, and consequently influenced the tension-compression performance of the extruded alloys. Co-extrusion process by introducing appropriate interfaces during extrusion was suggested as a sample and effective method to enhance the comprehensive mechanical properties of Mg-Al-Zn alloys.

A wood-like grain surface composite polymer profile (or wood-like profile) was fabricated by the extrusion moulding of melting multi-component polymers through a co-extrusion die, with two extruders feeding the co-extrusion die simultaneously. To improve the extrusion velocity uniformity of melting composite polymers, and decrease the distortion of wood-like grain profiles, this study treats the velocity equality among sub-regions in the wood-like profile cross-sections at the exit of the co-extrusion die as its optimisation objective. Meanwhile, the compression section gap, which exerts a significant influence on flow uniformity is selected as the design variable. Finite element numerical simulation and an ERP system are adopted to optimise the design in combination with a CAD/CAE network system co-extrusion die expert database of concurrent engineering. The optimisation design of case studies confirms that the velocity uniformity of the optimised wood-like grain profile melts presents a significant improvement in each sub-region at the exit of the co-extrusion die. Moreover, the distortion of composite profiles is decreased. The structural dimensions and performance of the composite profiles meet industrial demands.

This study investigates the effect of microencapsulation (via co-extrusion technology using high methoxyl pectin-enhanced alginate as a shell formulation) on the storage stability and antioxidant properties of kenaf seed oil. Microencapsulated kenaf seed oil (MKSO) and unencapsulated oil were stored at 25 °C for 28 days and at 65 °C for 24 days. The oils were then subjected to stability and quality evaluation based on peroxide, p-anisidine, and total oxidation values, conjugated diene and triene levels, thiobarbituric acid reactive substances, free fatty acids, total phenolic content, and the radical scavenging activity assays of 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid). The results showed that there was a significant increase (p

Continuous fibrous composite tapes of polyamide 6 (PA6)/polyethylene oxide (PEO) containing over 16 thousand individual ribbon-like PA6 micro-/nano-fiber domains were produced using a novel co-extrusion and two-dimensional multiplication technique. This melt-based process is suitable for scaling-up, applicable to any melt-processable polymers, and highly adjustable in terms of material composition, tape geometry, and number/size of the fiber domains. The PA6 fibrous tapes were post-oriented to achieve superior mechanical properties that are comparable with commercial strong polymeric fibrous composite tapes. The high tunability of tape and fiber structure and properties makes the co-extruded PA6/PEO tapes a desirable candidate for various strong tape applications.

In this study, Mg/Al composite rod with a thin 6082 aluminum alloy coated AZ31 magnesium alloy was successfully prepared by co-extrusion. Microstructure and texture of the extruded Mg/Al rod were systemically studied. A comparative study about electrochemical behavior of the Mg core and the Al sleeve was also addressed. Our results show that, co-extrusion can greatly refine grains of Mg alloy, but does not change the texture component. The 6082 sleeve exhibits a much better corrosion resistance than the AZ31 core. This study provided a novel approach to improve corrosion resistance of Mg alloy. The Al sleeve served as a barrier to protect the Mg alloy from corrosion.

In order to further solve the problem of the flow path of the head of the existing wood-plastic composite co-extrusion, the structural defects of the head are accurately found. This article first simulates the core and shell flow channels separately to simulate whether they are uniformly extruded and whether the exit speed is consistent. It is further analyzed that the cause of the uneven coating of the part is the problem of the shell flow channel and its structure. It does not meet the design requirements. Then, by proposing a variety of different flow channel structure optimization schemes, further simulations are performed, and the fluid flow trend is analyzed based on the simulation results. First of all it is determined that the existing flow path shape itself has problems. Considering the structure of the overall nozzle flow channel, based on the analysis of the flow channel trend, a new solution for the design of the co-extrusion ring flow channel is proposed. Further solve the structural problem of the coating head,which improved the design efficiency and reduced the waste of personnel and materials caused by continuous die testing. It has certain reference value for follow-up.

Cross-coupling reactions are among the most powerful C–C and C–X bond forming tools in organic chemistry. Traditionally, cross-coupling methods rely on the use of aryl halides or pseudohalides as electrophiles. In the past three years, decarbonylative cross-couplings of amides have emerged as an attractive method for the construction of a wide variety of carbon–carbon and carbon–heteroatom bonds, allowing for the synthetically-valuable functional group inter-conversion of the amide bond. These previously elusive reactions hinge upon selective activation of the N–C(O) acyl amide bond, followed by CO extrusion, in a formal double N–C/C–C bond activation, to generate a versatile aryl–metal intermediate as an attractive alternative to traditional cross-couplings of aryl halides and pseudohalides. In this perspective review, we present recent advances and key developments in the field of decarbonylative cross-coupling reactions of amides as well as discuss future challenges and potential applications for this exciting field.

In this paper, we present our progress in co-extrusion printing for fine-line metallization. With this technique, 30 µm wide and 20 µm tall front grid fingers are currently printed. Applied to industrial size cast silicon PERC solar cells, a world record conversion efficiency of 21.42% has been demonstrated. This result was achieved with a production-ready co-extrusion printer that runs at a throughput of 2700 wafers per hour. Furthermore, a printhead is presented that has been developed to enable co-extrusion printing on pseudo-square wafers. Finally the cost advantage of the technology is discussed.

There are a lot of different possibilities to manufacture polymer optical fibres. Regarding the final application, such as data transmission, lighting, or sensors, and the requirements concerning the polymer optical fibres, it is distinguished between step-index polymer optical fibres and graded-index polymer optical fibres. This chapter briefly summarizes the existing manufacturing techniques for step-index and graded-index polymer optical fibres and compares the advantages and the disadvantages of each process. At first the discontinuous manufacturing techniques for polymer optical fibres are discussed. These include preform production, heat drawing and batch extrusion. Finally the continuous manufacturing techniques are discussed. These include continuous extrusion, photochemical polymerization, co-extrusion, dry-spinning, melt-spinning and a modified melt-spinning process for the production of graded-index polymer optical fibres.